net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely)
[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) 2005-2008 by Pablo Neira Ayuso <pablo@netfilter.org>
8  *
9  * Initial connection tracking via netlink development funded and
10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
11  *
12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
13  *
14  * This software may be used and distributed according to the terms
15  * of the GNU General Public License, incorporated herein by reference.
16  */
17
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/rculist.h>
22 #include <linux/types.h>
23 #include <linux/timer.h>
24 #include <linux/skbuff.h>
25 #include <linux/errno.h>
26 #include <linux/netlink.h>
27 #include <linux/spinlock.h>
28 #include <linux/interrupt.h>
29 #include <linux/notifier.h>
30
31 #include <linux/netfilter.h>
32 #include <net/netlink.h>
33 #include <net/netfilter/nf_conntrack.h>
34 #include <net/netfilter/nf_conntrack_core.h>
35 #include <net/netfilter/nf_conntrack_expect.h>
36 #include <net/netfilter/nf_conntrack_helper.h>
37 #include <net/netfilter/nf_conntrack_l3proto.h>
38 #include <net/netfilter/nf_conntrack_l4proto.h>
39 #include <net/netfilter/nf_conntrack_tuple.h>
40 #include <net/netfilter/nf_conntrack_acct.h>
41 #ifdef CONFIG_NF_NAT_NEEDED
42 #include <net/netfilter/nf_nat_core.h>
43 #include <net/netfilter/nf_nat_protocol.h>
44 #endif
45
46 #include <linux/netfilter/nfnetlink.h>
47 #include <linux/netfilter/nfnetlink_conntrack.h>
48
49 MODULE_LICENSE("GPL");
50
51 static char __initdata version[] = "0.93";
52
53 static inline int
54 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
55                             const struct nf_conntrack_tuple *tuple,
56                             struct nf_conntrack_l4proto *l4proto)
57 {
58         int ret = 0;
59         struct nlattr *nest_parms;
60
61         nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
62         if (!nest_parms)
63                 goto nla_put_failure;
64         NLA_PUT_U8(skb, CTA_PROTO_NUM, tuple->dst.protonum);
65
66         if (likely(l4proto->tuple_to_nlattr))
67                 ret = l4proto->tuple_to_nlattr(skb, tuple);
68
69         nla_nest_end(skb, nest_parms);
70
71         return ret;
72
73 nla_put_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 nlattr *nest_parms;
84
85         nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
86         if (!nest_parms)
87                 goto nla_put_failure;
88
89         if (likely(l3proto->tuple_to_nlattr))
90                 ret = l3proto->tuple_to_nlattr(skb, tuple);
91
92         nla_nest_end(skb, nest_parms);
93
94         return ret;
95
96 nla_put_failure:
97         return -1;
98 }
99
100 static int
101 ctnetlink_dump_tuples(struct sk_buff *skb,
102                       const struct nf_conntrack_tuple *tuple)
103 {
104         int ret;
105         struct nf_conntrack_l3proto *l3proto;
106         struct nf_conntrack_l4proto *l4proto;
107
108         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
109         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
110         nf_ct_l3proto_put(l3proto);
111
112         if (unlikely(ret < 0))
113                 return ret;
114
115         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
116         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
117         nf_ct_l4proto_put(l4proto);
118
119         return ret;
120 }
121
122 static inline int
123 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
124 {
125         NLA_PUT_BE32(skb, CTA_STATUS, htonl(ct->status));
126         return 0;
127
128 nla_put_failure:
129         return -1;
130 }
131
132 static inline int
133 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
134 {
135         long timeout = (ct->timeout.expires - jiffies) / HZ;
136
137         if (timeout < 0)
138                 timeout = 0;
139
140         NLA_PUT_BE32(skb, CTA_TIMEOUT, htonl(timeout));
141         return 0;
142
143 nla_put_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;
151         struct nlattr *nest_proto;
152         int ret;
153
154         l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct));
155         if (!l4proto->to_nlattr) {
156                 nf_ct_l4proto_put(l4proto);
157                 return 0;
158         }
159
160         nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
161         if (!nest_proto)
162                 goto nla_put_failure;
163
164         ret = l4proto->to_nlattr(skb, nest_proto, ct);
165
166         nf_ct_l4proto_put(l4proto);
167
168         nla_nest_end(skb, nest_proto);
169
170         return ret;
171
172 nla_put_failure:
173         nf_ct_l4proto_put(l4proto);
174         return -1;
175 }
176
177 static inline int
178 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
179 {
180         struct nlattr *nest_helper;
181         const struct nf_conn_help *help = nfct_help(ct);
182         struct nf_conntrack_helper *helper;
183
184         if (!help)
185                 return 0;
186
187         rcu_read_lock();
188         helper = rcu_dereference(help->helper);
189         if (!helper)
190                 goto out;
191
192         nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
193         if (!nest_helper)
194                 goto nla_put_failure;
195         NLA_PUT_STRING(skb, CTA_HELP_NAME, helper->name);
196
197         if (helper->to_nlattr)
198                 helper->to_nlattr(skb, ct);
199
200         nla_nest_end(skb, nest_helper);
201 out:
202         rcu_read_unlock();
203         return 0;
204
205 nla_put_failure:
206         rcu_read_unlock();
207         return -1;
208 }
209
210 static int
211 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
212                         enum ip_conntrack_dir dir)
213 {
214         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
215         struct nlattr *nest_count;
216         const struct nf_conn_counter *acct;
217
218         acct = nf_conn_acct_find(ct);
219         if (!acct)
220                 return 0;
221
222         nest_count = nla_nest_start(skb, type | NLA_F_NESTED);
223         if (!nest_count)
224                 goto nla_put_failure;
225
226         NLA_PUT_BE64(skb, CTA_COUNTERS_PACKETS,
227                      cpu_to_be64(acct[dir].packets));
228         NLA_PUT_BE64(skb, CTA_COUNTERS_BYTES,
229                      cpu_to_be64(acct[dir].bytes));
230
231         nla_nest_end(skb, nest_count);
232
233         return 0;
234
235 nla_put_failure:
236         return -1;
237 }
238
239 #ifdef CONFIG_NF_CONNTRACK_MARK
240 static inline int
241 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
242 {
243         NLA_PUT_BE32(skb, CTA_MARK, htonl(ct->mark));
244         return 0;
245
246 nla_put_failure:
247         return -1;
248 }
249 #else
250 #define ctnetlink_dump_mark(a, b) (0)
251 #endif
252
253 #ifdef CONFIG_NF_CONNTRACK_SECMARK
254 static inline int
255 ctnetlink_dump_secmark(struct sk_buff *skb, const struct nf_conn *ct)
256 {
257         NLA_PUT_BE32(skb, CTA_SECMARK, htonl(ct->secmark));
258         return 0;
259
260 nla_put_failure:
261         return -1;
262 }
263 #else
264 #define ctnetlink_dump_secmark(a, b) (0)
265 #endif
266
267 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
268
269 static inline int
270 ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
271 {
272         struct nlattr *nest_parms;
273
274         if (!(ct->status & IPS_EXPECTED))
275                 return 0;
276
277         nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
278         if (!nest_parms)
279                 goto nla_put_failure;
280         if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
281                 goto nla_put_failure;
282         nla_nest_end(skb, nest_parms);
283
284         return 0;
285
286 nla_put_failure:
287         return -1;
288 }
289
290 #ifdef CONFIG_NF_NAT_NEEDED
291 static int
292 dump_nat_seq_adj(struct sk_buff *skb, const struct nf_nat_seq *natseq, int type)
293 {
294         struct nlattr *nest_parms;
295
296         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
297         if (!nest_parms)
298                 goto nla_put_failure;
299
300         NLA_PUT_BE32(skb, CTA_NAT_SEQ_CORRECTION_POS,
301                      htonl(natseq->correction_pos));
302         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_BEFORE,
303                      htonl(natseq->offset_before));
304         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_AFTER,
305                      htonl(natseq->offset_after));
306
307         nla_nest_end(skb, nest_parms);
308
309         return 0;
310
311 nla_put_failure:
312         return -1;
313 }
314
315 static inline int
316 ctnetlink_dump_nat_seq_adj(struct sk_buff *skb, const struct nf_conn *ct)
317 {
318         struct nf_nat_seq *natseq;
319         struct nf_conn_nat *nat = nfct_nat(ct);
320
321         if (!(ct->status & IPS_SEQ_ADJUST) || !nat)
322                 return 0;
323
324         natseq = &nat->seq[IP_CT_DIR_ORIGINAL];
325         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_ORIG) == -1)
326                 return -1;
327
328         natseq = &nat->seq[IP_CT_DIR_REPLY];
329         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_REPLY) == -1)
330                 return -1;
331
332         return 0;
333 }
334 #else
335 #define ctnetlink_dump_nat_seq_adj(a, b) (0)
336 #endif
337
338 static inline int
339 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
340 {
341         NLA_PUT_BE32(skb, CTA_ID, htonl((unsigned long)ct));
342         return 0;
343
344 nla_put_failure:
345         return -1;
346 }
347
348 static inline int
349 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
350 {
351         NLA_PUT_BE32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use)));
352         return 0;
353
354 nla_put_failure:
355         return -1;
356 }
357
358 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
359
360 static int
361 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
362                     int event, int nowait,
363                     const struct nf_conn *ct)
364 {
365         struct nlmsghdr *nlh;
366         struct nfgenmsg *nfmsg;
367         struct nlattr *nest_parms;
368         unsigned char *b = skb_tail_pointer(skb);
369
370         event |= NFNL_SUBSYS_CTNETLINK << 8;
371         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
372         nfmsg  = NLMSG_DATA(nlh);
373
374         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
375         nfmsg->nfgen_family = nf_ct_l3num(ct);
376         nfmsg->version      = NFNETLINK_V0;
377         nfmsg->res_id       = 0;
378
379         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
380         if (!nest_parms)
381                 goto nla_put_failure;
382         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
383                 goto nla_put_failure;
384         nla_nest_end(skb, nest_parms);
385
386         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
387         if (!nest_parms)
388                 goto nla_put_failure;
389         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
390                 goto nla_put_failure;
391         nla_nest_end(skb, nest_parms);
392
393         if (ctnetlink_dump_status(skb, ct) < 0 ||
394             ctnetlink_dump_timeout(skb, ct) < 0 ||
395             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
396             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
397             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
398             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
399             ctnetlink_dump_mark(skb, ct) < 0 ||
400             ctnetlink_dump_secmark(skb, ct) < 0 ||
401             ctnetlink_dump_id(skb, ct) < 0 ||
402             ctnetlink_dump_use(skb, ct) < 0 ||
403             ctnetlink_dump_master(skb, ct) < 0 ||
404             ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
405                 goto nla_put_failure;
406
407         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
408         return skb->len;
409
410 nlmsg_failure:
411 nla_put_failure:
412         nlmsg_trim(skb, b);
413         return -1;
414 }
415
416 #ifdef CONFIG_NF_CONNTRACK_EVENTS
417 static int ctnetlink_conntrack_event(struct notifier_block *this,
418                                      unsigned long events, void *ptr)
419 {
420         struct nlmsghdr *nlh;
421         struct nfgenmsg *nfmsg;
422         struct nlattr *nest_parms;
423         struct nf_conn *ct = (struct nf_conn *)ptr;
424         struct sk_buff *skb;
425         unsigned int type;
426         sk_buff_data_t b;
427         unsigned int flags = 0, group;
428
429         /* ignore our fake conntrack entry */
430         if (ct == &nf_conntrack_untracked)
431                 return NOTIFY_DONE;
432
433         if (events & IPCT_DESTROY) {
434                 type = IPCTNL_MSG_CT_DELETE;
435                 group = NFNLGRP_CONNTRACK_DESTROY;
436         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
437                 type = IPCTNL_MSG_CT_NEW;
438                 flags = NLM_F_CREATE|NLM_F_EXCL;
439                 group = NFNLGRP_CONNTRACK_NEW;
440         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
441                 type = IPCTNL_MSG_CT_NEW;
442                 group = NFNLGRP_CONNTRACK_UPDATE;
443         } else
444                 return NOTIFY_DONE;
445
446         if (!nfnetlink_has_listeners(group))
447                 return NOTIFY_DONE;
448
449         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
450         if (!skb)
451                 return NOTIFY_DONE;
452
453         b = skb->tail;
454
455         type |= NFNL_SUBSYS_CTNETLINK << 8;
456         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
457         nfmsg = NLMSG_DATA(nlh);
458
459         nlh->nlmsg_flags    = flags;
460         nfmsg->nfgen_family = nf_ct_l3num(ct);
461         nfmsg->version  = NFNETLINK_V0;
462         nfmsg->res_id   = 0;
463
464         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
465         if (!nest_parms)
466                 goto nla_put_failure;
467         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
468                 goto nla_put_failure;
469         nla_nest_end(skb, nest_parms);
470
471         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
472         if (!nest_parms)
473                 goto nla_put_failure;
474         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
475                 goto nla_put_failure;
476         nla_nest_end(skb, nest_parms);
477
478         if (ctnetlink_dump_id(skb, ct) < 0)
479                 goto nla_put_failure;
480
481         if (ctnetlink_dump_status(skb, ct) < 0)
482                 goto nla_put_failure;
483
484         if (events & IPCT_DESTROY) {
485                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
486                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
487                         goto nla_put_failure;
488         } else {
489                 if (ctnetlink_dump_timeout(skb, ct) < 0)
490                         goto nla_put_failure;
491
492                 if (events & IPCT_PROTOINFO
493                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
494                         goto nla_put_failure;
495
496                 if ((events & IPCT_HELPER || nfct_help(ct))
497                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
498                         goto nla_put_failure;
499
500 #ifdef CONFIG_NF_CONNTRACK_SECMARK
501                 if ((events & IPCT_SECMARK || ct->secmark)
502                     && ctnetlink_dump_secmark(skb, ct) < 0)
503                         goto nla_put_failure;
504 #endif
505
506                 if (events & IPCT_RELATED &&
507                     ctnetlink_dump_master(skb, ct) < 0)
508                         goto nla_put_failure;
509
510                 if (events & IPCT_NATSEQADJ &&
511                     ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
512                         goto nla_put_failure;
513         }
514
515 #ifdef CONFIG_NF_CONNTRACK_MARK
516         if ((events & IPCT_MARK || ct->mark)
517             && ctnetlink_dump_mark(skb, ct) < 0)
518                 goto nla_put_failure;
519 #endif
520
521         nlh->nlmsg_len = skb->tail - b;
522         nfnetlink_send(skb, 0, group, 0);
523         return NOTIFY_DONE;
524
525 nlmsg_failure:
526 nla_put_failure:
527         kfree_skb(skb);
528         return NOTIFY_DONE;
529 }
530 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
531
532 static int ctnetlink_done(struct netlink_callback *cb)
533 {
534         if (cb->args[1])
535                 nf_ct_put((struct nf_conn *)cb->args[1]);
536         return 0;
537 }
538
539 static int
540 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
541 {
542         struct nf_conn *ct, *last;
543         struct nf_conntrack_tuple_hash *h;
544         struct hlist_node *n;
545         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
546         u_int8_t l3proto = nfmsg->nfgen_family;
547
548         rcu_read_lock();
549         last = (struct nf_conn *)cb->args[1];
550         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
551 restart:
552                 hlist_for_each_entry_rcu(h, n, &init_net.ct.hash[cb->args[0]],
553                                          hnode) {
554                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
555                                 continue;
556                         ct = nf_ct_tuplehash_to_ctrack(h);
557                         /* Dump entries of a given L3 protocol number.
558                          * If it is not specified, ie. l3proto == 0,
559                          * then dump everything. */
560                         if (l3proto && nf_ct_l3num(ct) != l3proto)
561                                 continue;
562                         if (cb->args[1]) {
563                                 if (ct != last)
564                                         continue;
565                                 cb->args[1] = 0;
566                         }
567                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
568                                                 cb->nlh->nlmsg_seq,
569                                                 IPCTNL_MSG_CT_NEW,
570                                                 1, ct) < 0) {
571                                 if (!atomic_inc_not_zero(&ct->ct_general.use))
572                                         continue;
573                                 cb->args[1] = (unsigned long)ct;
574                                 goto out;
575                         }
576
577                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
578                                                 IPCTNL_MSG_CT_GET_CTRZERO) {
579                                 struct nf_conn_counter *acct;
580
581                                 acct = nf_conn_acct_find(ct);
582                                 if (acct)
583                                         memset(acct, 0, sizeof(struct nf_conn_counter[IP_CT_DIR_MAX]));
584                         }
585                 }
586                 if (cb->args[1]) {
587                         cb->args[1] = 0;
588                         goto restart;
589                 }
590         }
591 out:
592         rcu_read_unlock();
593         if (last)
594                 nf_ct_put(last);
595
596         return skb->len;
597 }
598
599 static inline int
600 ctnetlink_parse_tuple_ip(struct nlattr *attr, struct nf_conntrack_tuple *tuple)
601 {
602         struct nlattr *tb[CTA_IP_MAX+1];
603         struct nf_conntrack_l3proto *l3proto;
604         int ret = 0;
605
606         nla_parse_nested(tb, CTA_IP_MAX, attr, NULL);
607
608         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
609
610         if (likely(l3proto->nlattr_to_tuple)) {
611                 ret = nla_validate_nested(attr, CTA_IP_MAX,
612                                           l3proto->nla_policy);
613                 if (ret == 0)
614                         ret = l3proto->nlattr_to_tuple(tb, tuple);
615         }
616
617         nf_ct_l3proto_put(l3proto);
618
619         return ret;
620 }
621
622 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
623         [CTA_PROTO_NUM] = { .type = NLA_U8 },
624 };
625
626 static inline int
627 ctnetlink_parse_tuple_proto(struct nlattr *attr,
628                             struct nf_conntrack_tuple *tuple)
629 {
630         struct nlattr *tb[CTA_PROTO_MAX+1];
631         struct nf_conntrack_l4proto *l4proto;
632         int ret = 0;
633
634         ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy);
635         if (ret < 0)
636                 return ret;
637
638         if (!tb[CTA_PROTO_NUM])
639                 return -EINVAL;
640         tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
641
642         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
643
644         if (likely(l4proto->nlattr_to_tuple)) {
645                 ret = nla_validate_nested(attr, CTA_PROTO_MAX,
646                                           l4proto->nla_policy);
647                 if (ret == 0)
648                         ret = l4proto->nlattr_to_tuple(tb, tuple);
649         }
650
651         nf_ct_l4proto_put(l4proto);
652
653         return ret;
654 }
655
656 static int
657 ctnetlink_parse_tuple(struct nlattr *cda[], struct nf_conntrack_tuple *tuple,
658                       enum ctattr_tuple type, u_int8_t l3num)
659 {
660         struct nlattr *tb[CTA_TUPLE_MAX+1];
661         int err;
662
663         memset(tuple, 0, sizeof(*tuple));
664
665         nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], NULL);
666
667         if (!tb[CTA_TUPLE_IP])
668                 return -EINVAL;
669
670         tuple->src.l3num = l3num;
671
672         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
673         if (err < 0)
674                 return err;
675
676         if (!tb[CTA_TUPLE_PROTO])
677                 return -EINVAL;
678
679         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
680         if (err < 0)
681                 return err;
682
683         /* orig and expect tuples get DIR_ORIGINAL */
684         if (type == CTA_TUPLE_REPLY)
685                 tuple->dst.dir = IP_CT_DIR_REPLY;
686         else
687                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
688
689         return 0;
690 }
691
692 static inline int
693 ctnetlink_parse_help(struct nlattr *attr, char **helper_name)
694 {
695         struct nlattr *tb[CTA_HELP_MAX+1];
696
697         nla_parse_nested(tb, CTA_HELP_MAX, attr, NULL);
698
699         if (!tb[CTA_HELP_NAME])
700                 return -EINVAL;
701
702         *helper_name = nla_data(tb[CTA_HELP_NAME]);
703
704         return 0;
705 }
706
707 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
708         [CTA_STATUS]            = { .type = NLA_U32 },
709         [CTA_TIMEOUT]           = { .type = NLA_U32 },
710         [CTA_MARK]              = { .type = NLA_U32 },
711         [CTA_USE]               = { .type = NLA_U32 },
712         [CTA_ID]                = { .type = NLA_U32 },
713 };
714
715 static int
716 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
717                         struct nlmsghdr *nlh, struct nlattr *cda[])
718 {
719         struct nf_conntrack_tuple_hash *h;
720         struct nf_conntrack_tuple tuple;
721         struct nf_conn *ct;
722         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
723         u_int8_t u3 = nfmsg->nfgen_family;
724         int err = 0;
725
726         if (cda[CTA_TUPLE_ORIG])
727                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
728         else if (cda[CTA_TUPLE_REPLY])
729                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
730         else {
731                 /* Flush the whole table */
732                 nf_conntrack_flush(&init_net);
733                 return 0;
734         }
735
736         if (err < 0)
737                 return err;
738
739         h = nf_conntrack_find_get(&init_net, &tuple);
740         if (!h)
741                 return -ENOENT;
742
743         ct = nf_ct_tuplehash_to_ctrack(h);
744
745         if (cda[CTA_ID]) {
746                 u_int32_t id = ntohl(nla_get_be32(cda[CTA_ID]));
747                 if (id != (u32)(unsigned long)ct) {
748                         nf_ct_put(ct);
749                         return -ENOENT;
750                 }
751         }
752
753         nf_ct_kill(ct);
754         nf_ct_put(ct);
755
756         return 0;
757 }
758
759 static int
760 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
761                         struct nlmsghdr *nlh, struct nlattr *cda[])
762 {
763         struct nf_conntrack_tuple_hash *h;
764         struct nf_conntrack_tuple tuple;
765         struct nf_conn *ct;
766         struct sk_buff *skb2 = NULL;
767         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
768         u_int8_t u3 = nfmsg->nfgen_family;
769         int err = 0;
770
771         if (nlh->nlmsg_flags & NLM_F_DUMP)
772                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
773                                           ctnetlink_done);
774
775         if (cda[CTA_TUPLE_ORIG])
776                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
777         else if (cda[CTA_TUPLE_REPLY])
778                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
779         else
780                 return -EINVAL;
781
782         if (err < 0)
783                 return err;
784
785         h = nf_conntrack_find_get(&init_net, &tuple);
786         if (!h)
787                 return -ENOENT;
788
789         ct = nf_ct_tuplehash_to_ctrack(h);
790
791         err = -ENOMEM;
792         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
793         if (!skb2) {
794                 nf_ct_put(ct);
795                 return -ENOMEM;
796         }
797
798         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
799                                   IPCTNL_MSG_CT_NEW, 1, ct);
800         nf_ct_put(ct);
801         if (err <= 0)
802                 goto free;
803
804         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
805         if (err < 0)
806                 goto out;
807
808         return 0;
809
810 free:
811         kfree_skb(skb2);
812 out:
813         return err;
814 }
815
816 static int
817 ctnetlink_parse_nat_setup(struct nf_conn *ct,
818                           enum nf_nat_manip_type manip,
819                           struct nlattr *attr)
820 {
821         typeof(nfnetlink_parse_nat_setup_hook) parse_nat_setup;
822
823         parse_nat_setup = rcu_dereference(nfnetlink_parse_nat_setup_hook);
824         if (!parse_nat_setup) {
825 #ifdef CONFIG_MODULES
826                 rcu_read_unlock();
827                 nfnl_unlock();
828                 if (request_module("nf-nat-ipv4") < 0) {
829                         nfnl_lock();
830                         rcu_read_lock();
831                         return -EOPNOTSUPP;
832                 }
833                 nfnl_lock();
834                 rcu_read_lock();
835                 if (nfnetlink_parse_nat_setup_hook)
836                         return -EAGAIN;
837 #endif
838                 return -EOPNOTSUPP;
839         }
840
841         return parse_nat_setup(ct, manip, attr);
842 }
843
844 static int
845 ctnetlink_change_status(struct nf_conn *ct, struct nlattr *cda[])
846 {
847         unsigned long d;
848         unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
849         d = ct->status ^ status;
850
851         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
852                 /* unchangeable */
853                 return -EBUSY;
854
855         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
856                 /* SEEN_REPLY bit can only be set */
857                 return -EBUSY;
858
859         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
860                 /* ASSURED bit can only be set */
861                 return -EBUSY;
862
863         /* Be careful here, modifying NAT bits can screw up things,
864          * so don't let users modify them directly if they don't pass
865          * nf_nat_range. */
866         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
867         return 0;
868 }
869
870 static int
871 ctnetlink_change_nat(struct nf_conn *ct, struct nlattr *cda[])
872 {
873 #ifdef CONFIG_NF_NAT_NEEDED
874         int ret;
875
876         if (cda[CTA_NAT_DST]) {
877                 ret = ctnetlink_parse_nat_setup(ct,
878                                                 IP_NAT_MANIP_DST,
879                                                 cda[CTA_NAT_DST]);
880                 if (ret < 0)
881                         return ret;
882         }
883         if (cda[CTA_NAT_SRC]) {
884                 ret = ctnetlink_parse_nat_setup(ct,
885                                                 IP_NAT_MANIP_SRC,
886                                                 cda[CTA_NAT_SRC]);
887                 if (ret < 0)
888                         return ret;
889         }
890         return 0;
891 #else
892         return -EOPNOTSUPP;
893 #endif
894 }
895
896 static inline int
897 ctnetlink_change_helper(struct nf_conn *ct, struct nlattr *cda[])
898 {
899         struct nf_conntrack_helper *helper;
900         struct nf_conn_help *help = nfct_help(ct);
901         char *helpname;
902         int err;
903
904         /* don't change helper of sibling connections */
905         if (ct->master)
906                 return -EBUSY;
907
908         err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
909         if (err < 0)
910                 return err;
911
912         if (!strcmp(helpname, "")) {
913                 if (help && help->helper) {
914                         /* we had a helper before ... */
915                         nf_ct_remove_expectations(ct);
916                         rcu_assign_pointer(help->helper, NULL);
917                 }
918
919                 return 0;
920         }
921
922         helper = __nf_conntrack_helper_find_byname(helpname);
923         if (helper == NULL)
924                 return -EOPNOTSUPP;
925
926         if (help) {
927                 if (help->helper == helper)
928                         return 0;
929                 if (help->helper)
930                         return -EBUSY;
931                 /* need to zero data of old helper */
932                 memset(&help->help, 0, sizeof(help->help));
933         } else {
934                 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
935                 if (help == NULL)
936                         return -ENOMEM;
937         }
938
939         rcu_assign_pointer(help->helper, helper);
940
941         return 0;
942 }
943
944 static inline int
945 ctnetlink_change_timeout(struct nf_conn *ct, struct nlattr *cda[])
946 {
947         u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
948
949         if (!del_timer(&ct->timeout))
950                 return -ETIME;
951
952         ct->timeout.expires = jiffies + timeout * HZ;
953         add_timer(&ct->timeout);
954
955         return 0;
956 }
957
958 static inline int
959 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nlattr *cda[])
960 {
961         struct nlattr *tb[CTA_PROTOINFO_MAX+1], *attr = cda[CTA_PROTOINFO];
962         struct nf_conntrack_l4proto *l4proto;
963         int err = 0;
964
965         nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, NULL);
966
967         l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct));
968         if (l4proto->from_nlattr)
969                 err = l4proto->from_nlattr(tb, ct);
970         nf_ct_l4proto_put(l4proto);
971
972         return err;
973 }
974
975 #ifdef CONFIG_NF_NAT_NEEDED
976 static inline int
977 change_nat_seq_adj(struct nf_nat_seq *natseq, struct nlattr *attr)
978 {
979         struct nlattr *cda[CTA_NAT_SEQ_MAX+1];
980
981         nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, NULL);
982
983         if (!cda[CTA_NAT_SEQ_CORRECTION_POS])
984                 return -EINVAL;
985
986         natseq->correction_pos =
987                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_CORRECTION_POS]));
988
989         if (!cda[CTA_NAT_SEQ_OFFSET_BEFORE])
990                 return -EINVAL;
991
992         natseq->offset_before =
993                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_BEFORE]));
994
995         if (!cda[CTA_NAT_SEQ_OFFSET_AFTER])
996                 return -EINVAL;
997
998         natseq->offset_after =
999                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_AFTER]));
1000
1001         return 0;
1002 }
1003
1004 static int
1005 ctnetlink_change_nat_seq_adj(struct nf_conn *ct, struct nlattr *cda[])
1006 {
1007         int ret = 0;
1008         struct nf_conn_nat *nat = nfct_nat(ct);
1009
1010         if (!nat)
1011                 return 0;
1012
1013         if (cda[CTA_NAT_SEQ_ADJ_ORIG]) {
1014                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_ORIGINAL],
1015                                          cda[CTA_NAT_SEQ_ADJ_ORIG]);
1016                 if (ret < 0)
1017                         return ret;
1018
1019                 ct->status |= IPS_SEQ_ADJUST;
1020         }
1021
1022         if (cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1023                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_REPLY],
1024                                          cda[CTA_NAT_SEQ_ADJ_REPLY]);
1025                 if (ret < 0)
1026                         return ret;
1027
1028                 ct->status |= IPS_SEQ_ADJUST;
1029         }
1030
1031         return 0;
1032 }
1033 #endif
1034
1035 static int
1036 ctnetlink_change_conntrack(struct nf_conn *ct, struct nlattr *cda[])
1037 {
1038         int err;
1039
1040         if (cda[CTA_HELP]) {
1041                 err = ctnetlink_change_helper(ct, cda);
1042                 if (err < 0)
1043                         return err;
1044         }
1045
1046         if (cda[CTA_TIMEOUT]) {
1047                 err = ctnetlink_change_timeout(ct, cda);
1048                 if (err < 0)
1049                         return err;
1050         }
1051
1052         if (cda[CTA_STATUS]) {
1053                 err = ctnetlink_change_status(ct, cda);
1054                 if (err < 0)
1055                         return err;
1056         }
1057
1058         if (cda[CTA_PROTOINFO]) {
1059                 err = ctnetlink_change_protoinfo(ct, cda);
1060                 if (err < 0)
1061                         return err;
1062         }
1063
1064 #if defined(CONFIG_NF_CONNTRACK_MARK)
1065         if (cda[CTA_MARK])
1066                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1067 #endif
1068
1069 #ifdef CONFIG_NF_NAT_NEEDED
1070         if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1071                 err = ctnetlink_change_nat_seq_adj(ct, cda);
1072                 if (err < 0)
1073                         return err;
1074         }
1075 #endif
1076
1077         return 0;
1078 }
1079
1080 static int
1081 ctnetlink_create_conntrack(struct nlattr *cda[],
1082                            struct nf_conntrack_tuple *otuple,
1083                            struct nf_conntrack_tuple *rtuple,
1084                            struct nf_conn *master_ct)
1085 {
1086         struct nf_conn *ct;
1087         int err = -EINVAL;
1088         struct nf_conn_help *help;
1089         struct nf_conntrack_helper *helper;
1090
1091         ct = nf_conntrack_alloc(&init_net, otuple, rtuple, GFP_KERNEL);
1092         if (ct == NULL || IS_ERR(ct))
1093                 return -ENOMEM;
1094
1095         if (!cda[CTA_TIMEOUT])
1096                 goto err;
1097         ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1098
1099         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1100         ct->status |= IPS_CONFIRMED;
1101
1102         rcu_read_lock();
1103         helper = __nf_ct_helper_find(rtuple);
1104         if (helper) {
1105                 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
1106                 if (help == NULL) {
1107                         rcu_read_unlock();
1108                         err = -ENOMEM;
1109                         goto err;
1110                 }
1111                 /* not in hash table yet so not strictly necessary */
1112                 rcu_assign_pointer(help->helper, helper);
1113         }
1114
1115         if (cda[CTA_STATUS]) {
1116                 err = ctnetlink_change_status(ct, cda);
1117                 if (err < 0) {
1118                         rcu_read_unlock();
1119                         goto err;
1120                 }
1121         }
1122
1123         if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
1124                 err = ctnetlink_change_nat(ct, cda);
1125                 if (err < 0) {
1126                         rcu_read_unlock();
1127                         goto err;
1128                 }
1129         }
1130
1131         if (cda[CTA_PROTOINFO]) {
1132                 err = ctnetlink_change_protoinfo(ct, cda);
1133                 if (err < 0) {
1134                         rcu_read_unlock();
1135                         goto err;
1136                 }
1137         }
1138
1139         nf_ct_acct_ext_add(ct, GFP_KERNEL);
1140
1141 #if defined(CONFIG_NF_CONNTRACK_MARK)
1142         if (cda[CTA_MARK])
1143                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1144 #endif
1145
1146         /* setup master conntrack: this is a confirmed expectation */
1147         if (master_ct) {
1148                 __set_bit(IPS_EXPECTED_BIT, &ct->status);
1149                 ct->master = master_ct;
1150         }
1151
1152         add_timer(&ct->timeout);
1153         nf_conntrack_hash_insert(ct);
1154         rcu_read_unlock();
1155
1156         return 0;
1157
1158 err:
1159         nf_conntrack_free(ct);
1160         return err;
1161 }
1162
1163 static int
1164 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1165                         struct nlmsghdr *nlh, struct nlattr *cda[])
1166 {
1167         struct nf_conntrack_tuple otuple, rtuple;
1168         struct nf_conntrack_tuple_hash *h = NULL;
1169         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1170         u_int8_t u3 = nfmsg->nfgen_family;
1171         int err = 0;
1172
1173         if (cda[CTA_TUPLE_ORIG]) {
1174                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1175                 if (err < 0)
1176                         return err;
1177         }
1178
1179         if (cda[CTA_TUPLE_REPLY]) {
1180                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1181                 if (err < 0)
1182                         return err;
1183         }
1184
1185         spin_lock_bh(&nf_conntrack_lock);
1186         if (cda[CTA_TUPLE_ORIG])
1187                 h = __nf_conntrack_find(&init_net, &otuple);
1188         else if (cda[CTA_TUPLE_REPLY])
1189                 h = __nf_conntrack_find(&init_net, &rtuple);
1190
1191         if (h == NULL) {
1192                 struct nf_conntrack_tuple master;
1193                 struct nf_conntrack_tuple_hash *master_h = NULL;
1194                 struct nf_conn *master_ct = NULL;
1195
1196                 if (cda[CTA_TUPLE_MASTER]) {
1197                         err = ctnetlink_parse_tuple(cda,
1198                                                     &master,
1199                                                     CTA_TUPLE_MASTER,
1200                                                     u3);
1201                         if (err < 0)
1202                                 goto out_unlock;
1203
1204                         master_h = __nf_conntrack_find(&init_net, &master);
1205                         if (master_h == NULL) {
1206                                 err = -ENOENT;
1207                                 goto out_unlock;
1208                         }
1209                         master_ct = nf_ct_tuplehash_to_ctrack(master_h);
1210                         atomic_inc(&master_ct->ct_general.use);
1211                 }
1212
1213                 spin_unlock_bh(&nf_conntrack_lock);
1214                 err = -ENOENT;
1215                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1216                         err = ctnetlink_create_conntrack(cda,
1217                                                          &otuple,
1218                                                          &rtuple,
1219                                                          master_ct);
1220                 if (err < 0 && master_ct)
1221                         nf_ct_put(master_ct);
1222
1223                 return err;
1224         }
1225         /* implicit 'else' */
1226
1227         /* We manipulate the conntrack inside the global conntrack table lock,
1228          * so there's no need to increase the refcount */
1229         err = -EEXIST;
1230         if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
1231                 /* we only allow nat config for new conntracks */
1232                 if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
1233                         err = -EOPNOTSUPP;
1234                         goto out_unlock;
1235                 }
1236                 /* can't link an existing conntrack to a master */
1237                 if (cda[CTA_TUPLE_MASTER]) {
1238                         err = -EOPNOTSUPP;
1239                         goto out_unlock;
1240                 }
1241                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h),
1242                                                  cda);
1243         }
1244
1245 out_unlock:
1246         spin_unlock_bh(&nf_conntrack_lock);
1247         return err;
1248 }
1249
1250 /***********************************************************************
1251  * EXPECT
1252  ***********************************************************************/
1253
1254 static inline int
1255 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1256                          const struct nf_conntrack_tuple *tuple,
1257                          enum ctattr_expect type)
1258 {
1259         struct nlattr *nest_parms;
1260
1261         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
1262         if (!nest_parms)
1263                 goto nla_put_failure;
1264         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1265                 goto nla_put_failure;
1266         nla_nest_end(skb, nest_parms);
1267
1268         return 0;
1269
1270 nla_put_failure:
1271         return -1;
1272 }
1273
1274 static inline int
1275 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1276                         const struct nf_conntrack_tuple *tuple,
1277                         const struct nf_conntrack_tuple_mask *mask)
1278 {
1279         int ret;
1280         struct nf_conntrack_l3proto *l3proto;
1281         struct nf_conntrack_l4proto *l4proto;
1282         struct nf_conntrack_tuple m;
1283         struct nlattr *nest_parms;
1284
1285         memset(&m, 0xFF, sizeof(m));
1286         m.src.u.all = mask->src.u.all;
1287         memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
1288
1289         nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
1290         if (!nest_parms)
1291                 goto nla_put_failure;
1292
1293         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1294         ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
1295         nf_ct_l3proto_put(l3proto);
1296
1297         if (unlikely(ret < 0))
1298                 goto nla_put_failure;
1299
1300         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1301         ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
1302         nf_ct_l4proto_put(l4proto);
1303         if (unlikely(ret < 0))
1304                 goto nla_put_failure;
1305
1306         nla_nest_end(skb, nest_parms);
1307
1308         return 0;
1309
1310 nla_put_failure:
1311         return -1;
1312 }
1313
1314 static int
1315 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1316                           const struct nf_conntrack_expect *exp)
1317 {
1318         struct nf_conn *master = exp->master;
1319         long timeout = (exp->timeout.expires - jiffies) / HZ;
1320
1321         if (timeout < 0)
1322                 timeout = 0;
1323
1324         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1325                 goto nla_put_failure;
1326         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1327                 goto nla_put_failure;
1328         if (ctnetlink_exp_dump_tuple(skb,
1329                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1330                                  CTA_EXPECT_MASTER) < 0)
1331                 goto nla_put_failure;
1332
1333         NLA_PUT_BE32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout));
1334         NLA_PUT_BE32(skb, CTA_EXPECT_ID, htonl((unsigned long)exp));
1335
1336         return 0;
1337
1338 nla_put_failure:
1339         return -1;
1340 }
1341
1342 static int
1343 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1344                     int event,
1345                     int nowait,
1346                     const struct nf_conntrack_expect *exp)
1347 {
1348         struct nlmsghdr *nlh;
1349         struct nfgenmsg *nfmsg;
1350         unsigned char *b = skb_tail_pointer(skb);
1351
1352         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1353         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1354         nfmsg  = NLMSG_DATA(nlh);
1355
1356         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1357         nfmsg->nfgen_family = exp->tuple.src.l3num;
1358         nfmsg->version      = NFNETLINK_V0;
1359         nfmsg->res_id       = 0;
1360
1361         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1362                 goto nla_put_failure;
1363
1364         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1365         return skb->len;
1366
1367 nlmsg_failure:
1368 nla_put_failure:
1369         nlmsg_trim(skb, b);
1370         return -1;
1371 }
1372
1373 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1374 static int ctnetlink_expect_event(struct notifier_block *this,
1375                                   unsigned long events, void *ptr)
1376 {
1377         struct nlmsghdr *nlh;
1378         struct nfgenmsg *nfmsg;
1379         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1380         struct sk_buff *skb;
1381         unsigned int type;
1382         sk_buff_data_t b;
1383         int flags = 0;
1384
1385         if (events & IPEXP_NEW) {
1386                 type = IPCTNL_MSG_EXP_NEW;
1387                 flags = NLM_F_CREATE|NLM_F_EXCL;
1388         } else
1389                 return NOTIFY_DONE;
1390
1391         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1392                 return NOTIFY_DONE;
1393
1394         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1395         if (!skb)
1396                 return NOTIFY_DONE;
1397
1398         b = skb->tail;
1399
1400         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1401         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1402         nfmsg = NLMSG_DATA(nlh);
1403
1404         nlh->nlmsg_flags    = flags;
1405         nfmsg->nfgen_family = exp->tuple.src.l3num;
1406         nfmsg->version      = NFNETLINK_V0;
1407         nfmsg->res_id       = 0;
1408
1409         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1410                 goto nla_put_failure;
1411
1412         nlh->nlmsg_len = skb->tail - b;
1413         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1414         return NOTIFY_DONE;
1415
1416 nlmsg_failure:
1417 nla_put_failure:
1418         kfree_skb(skb);
1419         return NOTIFY_DONE;
1420 }
1421 #endif
1422 static int ctnetlink_exp_done(struct netlink_callback *cb)
1423 {
1424         if (cb->args[1])
1425                 nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
1426         return 0;
1427 }
1428
1429 static int
1430 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1431 {
1432         struct net *net = &init_net;
1433         struct nf_conntrack_expect *exp, *last;
1434         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1435         struct hlist_node *n;
1436         u_int8_t l3proto = nfmsg->nfgen_family;
1437
1438         rcu_read_lock();
1439         last = (struct nf_conntrack_expect *)cb->args[1];
1440         for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
1441 restart:
1442                 hlist_for_each_entry(exp, n, &net->ct.expect_hash[cb->args[0]],
1443                                      hnode) {
1444                         if (l3proto && exp->tuple.src.l3num != l3proto)
1445                                 continue;
1446                         if (cb->args[1]) {
1447                                 if (exp != last)
1448                                         continue;
1449                                 cb->args[1] = 0;
1450                         }
1451                         if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1452                                                     cb->nlh->nlmsg_seq,
1453                                                     IPCTNL_MSG_EXP_NEW,
1454                                                     1, exp) < 0) {
1455                                 if (!atomic_inc_not_zero(&exp->use))
1456                                         continue;
1457                                 cb->args[1] = (unsigned long)exp;
1458                                 goto out;
1459                         }
1460                 }
1461                 if (cb->args[1]) {
1462                         cb->args[1] = 0;
1463                         goto restart;
1464                 }
1465         }
1466 out:
1467         rcu_read_unlock();
1468         if (last)
1469                 nf_ct_expect_put(last);
1470
1471         return skb->len;
1472 }
1473
1474 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
1475         [CTA_EXPECT_TIMEOUT]    = { .type = NLA_U32 },
1476         [CTA_EXPECT_ID]         = { .type = NLA_U32 },
1477 };
1478
1479 static int
1480 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1481                      struct nlmsghdr *nlh, struct nlattr *cda[])
1482 {
1483         struct nf_conntrack_tuple tuple;
1484         struct nf_conntrack_expect *exp;
1485         struct sk_buff *skb2;
1486         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1487         u_int8_t u3 = nfmsg->nfgen_family;
1488         int err = 0;
1489
1490         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1491                 return netlink_dump_start(ctnl, skb, nlh,
1492                                           ctnetlink_exp_dump_table,
1493                                           ctnetlink_exp_done);
1494         }
1495
1496         if (cda[CTA_EXPECT_MASTER])
1497                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1498         else
1499                 return -EINVAL;
1500
1501         if (err < 0)
1502                 return err;
1503
1504         exp = nf_ct_expect_find_get(&init_net, &tuple);
1505         if (!exp)
1506                 return -ENOENT;
1507
1508         if (cda[CTA_EXPECT_ID]) {
1509                 __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1510                 if (ntohl(id) != (u32)(unsigned long)exp) {
1511                         nf_ct_expect_put(exp);
1512                         return -ENOENT;
1513                 }
1514         }
1515
1516         err = -ENOMEM;
1517         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1518         if (!skb2)
1519                 goto out;
1520
1521         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1522                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1523                                       1, exp);
1524         if (err <= 0)
1525                 goto free;
1526
1527         nf_ct_expect_put(exp);
1528
1529         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1530
1531 free:
1532         kfree_skb(skb2);
1533 out:
1534         nf_ct_expect_put(exp);
1535         return err;
1536 }
1537
1538 static int
1539 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1540                      struct nlmsghdr *nlh, struct nlattr *cda[])
1541 {
1542         struct nf_conntrack_expect *exp;
1543         struct nf_conntrack_tuple tuple;
1544         struct nf_conntrack_helper *h;
1545         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1546         struct hlist_node *n, *next;
1547         u_int8_t u3 = nfmsg->nfgen_family;
1548         unsigned int i;
1549         int err;
1550
1551         if (cda[CTA_EXPECT_TUPLE]) {
1552                 /* delete a single expect by tuple */
1553                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1554                 if (err < 0)
1555                         return err;
1556
1557                 /* bump usage count to 2 */
1558                 exp = nf_ct_expect_find_get(&init_net, &tuple);
1559                 if (!exp)
1560                         return -ENOENT;
1561
1562                 if (cda[CTA_EXPECT_ID]) {
1563                         __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1564                         if (ntohl(id) != (u32)(unsigned long)exp) {
1565                                 nf_ct_expect_put(exp);
1566                                 return -ENOENT;
1567                         }
1568                 }
1569
1570                 /* after list removal, usage count == 1 */
1571                 nf_ct_unexpect_related(exp);
1572                 /* have to put what we 'get' above.
1573                  * after this line usage count == 0 */
1574                 nf_ct_expect_put(exp);
1575         } else if (cda[CTA_EXPECT_HELP_NAME]) {
1576                 char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
1577                 struct nf_conn_help *m_help;
1578
1579                 /* delete all expectations for this helper */
1580                 spin_lock_bh(&nf_conntrack_lock);
1581                 h = __nf_conntrack_helper_find_byname(name);
1582                 if (!h) {
1583                         spin_unlock_bh(&nf_conntrack_lock);
1584                         return -EOPNOTSUPP;
1585                 }
1586                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1587                         hlist_for_each_entry_safe(exp, n, next,
1588                                                   &init_net.ct.expect_hash[i],
1589                                                   hnode) {
1590                                 m_help = nfct_help(exp->master);
1591                                 if (m_help->helper == h
1592                                     && del_timer(&exp->timeout)) {
1593                                         nf_ct_unlink_expect(exp);
1594                                         nf_ct_expect_put(exp);
1595                                 }
1596                         }
1597                 }
1598                 spin_unlock_bh(&nf_conntrack_lock);
1599         } else {
1600                 /* This basically means we have to flush everything*/
1601                 spin_lock_bh(&nf_conntrack_lock);
1602                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1603                         hlist_for_each_entry_safe(exp, n, next,
1604                                                   &init_net.ct.expect_hash[i],
1605                                                   hnode) {
1606                                 if (del_timer(&exp->timeout)) {
1607                                         nf_ct_unlink_expect(exp);
1608                                         nf_ct_expect_put(exp);
1609                                 }
1610                         }
1611                 }
1612                 spin_unlock_bh(&nf_conntrack_lock);
1613         }
1614
1615         return 0;
1616 }
1617 static int
1618 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nlattr *cda[])
1619 {
1620         return -EOPNOTSUPP;
1621 }
1622
1623 static int
1624 ctnetlink_create_expect(struct nlattr *cda[], u_int8_t u3)
1625 {
1626         struct nf_conntrack_tuple tuple, mask, master_tuple;
1627         struct nf_conntrack_tuple_hash *h = NULL;
1628         struct nf_conntrack_expect *exp;
1629         struct nf_conn *ct;
1630         struct nf_conn_help *help;
1631         int err = 0;
1632
1633         /* caller guarantees that those three CTA_EXPECT_* exist */
1634         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1635         if (err < 0)
1636                 return err;
1637         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1638         if (err < 0)
1639                 return err;
1640         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1641         if (err < 0)
1642                 return err;
1643
1644         /* Look for master conntrack of this expectation */
1645         h = nf_conntrack_find_get(&init_net, &master_tuple);
1646         if (!h)
1647                 return -ENOENT;
1648         ct = nf_ct_tuplehash_to_ctrack(h);
1649         help = nfct_help(ct);
1650
1651         if (!help || !help->helper) {
1652                 /* such conntrack hasn't got any helper, abort */
1653                 err = -EINVAL;
1654                 goto out;
1655         }
1656
1657         exp = nf_ct_expect_alloc(ct);
1658         if (!exp) {
1659                 err = -ENOMEM;
1660                 goto out;
1661         }
1662
1663         exp->expectfn = NULL;
1664         exp->flags = 0;
1665         exp->master = ct;
1666         exp->helper = NULL;
1667         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1668         memcpy(&exp->mask.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3));
1669         exp->mask.src.u.all = mask.src.u.all;
1670
1671         err = nf_ct_expect_related(exp);
1672         nf_ct_expect_put(exp);
1673
1674 out:
1675         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1676         return err;
1677 }
1678
1679 static int
1680 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1681                      struct nlmsghdr *nlh, struct nlattr *cda[])
1682 {
1683         struct nf_conntrack_tuple tuple;
1684         struct nf_conntrack_expect *exp;
1685         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1686         u_int8_t u3 = nfmsg->nfgen_family;
1687         int err = 0;
1688
1689         if (!cda[CTA_EXPECT_TUPLE]
1690             || !cda[CTA_EXPECT_MASK]
1691             || !cda[CTA_EXPECT_MASTER])
1692                 return -EINVAL;
1693
1694         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1695         if (err < 0)
1696                 return err;
1697
1698         spin_lock_bh(&nf_conntrack_lock);
1699         exp = __nf_ct_expect_find(&init_net, &tuple);
1700
1701         if (!exp) {
1702                 spin_unlock_bh(&nf_conntrack_lock);
1703                 err = -ENOENT;
1704                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1705                         err = ctnetlink_create_expect(cda, u3);
1706                 return err;
1707         }
1708
1709         err = -EEXIST;
1710         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1711                 err = ctnetlink_change_expect(exp, cda);
1712         spin_unlock_bh(&nf_conntrack_lock);
1713
1714         return err;
1715 }
1716
1717 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1718 static struct notifier_block ctnl_notifier = {
1719         .notifier_call  = ctnetlink_conntrack_event,
1720 };
1721
1722 static struct notifier_block ctnl_notifier_exp = {
1723         .notifier_call  = ctnetlink_expect_event,
1724 };
1725 #endif
1726
1727 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1728         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1729                                             .attr_count = CTA_MAX,
1730                                             .policy = ct_nla_policy },
1731         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1732                                             .attr_count = CTA_MAX,
1733                                             .policy = ct_nla_policy },
1734         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1735                                             .attr_count = CTA_MAX,
1736                                             .policy = ct_nla_policy },
1737         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1738                                             .attr_count = CTA_MAX,
1739                                             .policy = ct_nla_policy },
1740 };
1741
1742 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1743         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1744                                             .attr_count = CTA_EXPECT_MAX,
1745                                             .policy = exp_nla_policy },
1746         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1747                                             .attr_count = CTA_EXPECT_MAX,
1748                                             .policy = exp_nla_policy },
1749         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1750                                             .attr_count = CTA_EXPECT_MAX,
1751                                             .policy = exp_nla_policy },
1752 };
1753
1754 static const struct nfnetlink_subsystem ctnl_subsys = {
1755         .name                           = "conntrack",
1756         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1757         .cb_count                       = IPCTNL_MSG_MAX,
1758         .cb                             = ctnl_cb,
1759 };
1760
1761 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
1762         .name                           = "conntrack_expect",
1763         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1764         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1765         .cb                             = ctnl_exp_cb,
1766 };
1767
1768 MODULE_ALIAS("ip_conntrack_netlink");
1769 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1770 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1771
1772 static int __init ctnetlink_init(void)
1773 {
1774         int ret;
1775
1776         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1777         ret = nfnetlink_subsys_register(&ctnl_subsys);
1778         if (ret < 0) {
1779                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1780                 goto err_out;
1781         }
1782
1783         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1784         if (ret < 0) {
1785                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1786                 goto err_unreg_subsys;
1787         }
1788
1789 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1790         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1791         if (ret < 0) {
1792                 printk("ctnetlink_init: cannot register notifier.\n");
1793                 goto err_unreg_exp_subsys;
1794         }
1795
1796         ret = nf_ct_expect_register_notifier(&ctnl_notifier_exp);
1797         if (ret < 0) {
1798                 printk("ctnetlink_init: cannot expect register notifier.\n");
1799                 goto err_unreg_notifier;
1800         }
1801 #endif
1802
1803         return 0;
1804
1805 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1806 err_unreg_notifier:
1807         nf_conntrack_unregister_notifier(&ctnl_notifier);
1808 err_unreg_exp_subsys:
1809         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1810 #endif
1811 err_unreg_subsys:
1812         nfnetlink_subsys_unregister(&ctnl_subsys);
1813 err_out:
1814         return ret;
1815 }
1816
1817 static void __exit ctnetlink_exit(void)
1818 {
1819         printk("ctnetlink: unregistering from nfnetlink.\n");
1820
1821 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1822         nf_ct_expect_unregister_notifier(&ctnl_notifier_exp);
1823         nf_conntrack_unregister_notifier(&ctnl_notifier);
1824 #endif
1825
1826         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1827         nfnetlink_subsys_unregister(&ctnl_subsys);
1828         return;
1829 }
1830
1831 module_init(ctnetlink_init);
1832 module_exit(ctnetlink_exit);