[NETFILTER]: ctnetlink: clear helper area and handle unchanged helper
[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  * Initial connection tracking via netlink development funded and
10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
11  *
12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
13  *
14  * This software may be used and distributed according to the terms
15  * of the GNU General Public License, incorporated herein by reference.
16  */
17
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/types.h>
22 #include <linux/timer.h>
23 #include <linux/skbuff.h>
24 #include <linux/errno.h>
25 #include <linux/netlink.h>
26 #include <linux/spinlock.h>
27 #include <linux/interrupt.h>
28 #include <linux/notifier.h>
29
30 #include <linux/netfilter.h>
31 #include <net/netlink.h>
32 #include <net/netfilter/nf_conntrack.h>
33 #include <net/netfilter/nf_conntrack_core.h>
34 #include <net/netfilter/nf_conntrack_expect.h>
35 #include <net/netfilter/nf_conntrack_helper.h>
36 #include <net/netfilter/nf_conntrack_l3proto.h>
37 #include <net/netfilter/nf_conntrack_l4proto.h>
38 #include <net/netfilter/nf_conntrack_tuple.h>
39 #ifdef CONFIG_NF_NAT_NEEDED
40 #include <net/netfilter/nf_nat_core.h>
41 #include <net/netfilter/nf_nat_protocol.h>
42 #endif
43
44 #include <linux/netfilter/nfnetlink.h>
45 #include <linux/netfilter/nfnetlink_conntrack.h>
46
47 MODULE_LICENSE("GPL");
48
49 static char __initdata version[] = "0.93";
50
51 static inline int
52 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
53                             const struct nf_conntrack_tuple *tuple,
54                             struct nf_conntrack_l4proto *l4proto)
55 {
56         int ret = 0;
57         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
58
59         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
60
61         if (likely(l4proto->tuple_to_nfattr))
62                 ret = l4proto->tuple_to_nfattr(skb, tuple);
63
64         NFA_NEST_END(skb, nest_parms);
65
66         return ret;
67
68 nfattr_failure:
69         return -1;
70 }
71
72 static inline int
73 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
74                          const struct nf_conntrack_tuple *tuple,
75                          struct nf_conntrack_l3proto *l3proto)
76 {
77         int ret = 0;
78         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
79
80         if (likely(l3proto->tuple_to_nfattr))
81                 ret = l3proto->tuple_to_nfattr(skb, tuple);
82
83         NFA_NEST_END(skb, nest_parms);
84
85         return ret;
86
87 nfattr_failure:
88         return -1;
89 }
90
91 static inline int
92 ctnetlink_dump_tuples(struct sk_buff *skb,
93                       const struct nf_conntrack_tuple *tuple)
94 {
95         int ret;
96         struct nf_conntrack_l3proto *l3proto;
97         struct nf_conntrack_l4proto *l4proto;
98
99         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
100         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
101         nf_ct_l3proto_put(l3proto);
102
103         if (unlikely(ret < 0))
104                 return ret;
105
106         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
107         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
108         nf_ct_l4proto_put(l4proto);
109
110         return ret;
111 }
112
113 static inline int
114 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
115 {
116         __be32 status = htonl((u_int32_t) ct->status);
117         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
118         return 0;
119
120 nfattr_failure:
121         return -1;
122 }
123
124 static inline int
125 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
126 {
127         long timeout_l = ct->timeout.expires - jiffies;
128         __be32 timeout;
129
130         if (timeout_l < 0)
131                 timeout = 0;
132         else
133                 timeout = htonl(timeout_l / HZ);
134
135         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
136         return 0;
137
138 nfattr_failure:
139         return -1;
140 }
141
142 static inline int
143 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
144 {
145         struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
146         struct nfattr *nest_proto;
147         int ret;
148
149         if (!l4proto->to_nfattr) {
150                 nf_ct_l4proto_put(l4proto);
151                 return 0;
152         }
153
154         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
155
156         ret = l4proto->to_nfattr(skb, nest_proto, ct);
157
158         nf_ct_l4proto_put(l4proto);
159
160         NFA_NEST_END(skb, nest_proto);
161
162         return ret;
163
164 nfattr_failure:
165         nf_ct_l4proto_put(l4proto);
166         return -1;
167 }
168
169 static inline int
170 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
171 {
172         struct nfattr *nest_helper;
173         const struct nf_conn_help *help = nfct_help(ct);
174
175         if (!help || !help->helper)
176                 return 0;
177
178         nest_helper = NFA_NEST(skb, CTA_HELP);
179         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
180
181         if (help->helper->to_nfattr)
182                 help->helper->to_nfattr(skb, ct);
183
184         NFA_NEST_END(skb, nest_helper);
185
186         return 0;
187
188 nfattr_failure:
189         return -1;
190 }
191
192 #ifdef CONFIG_NF_CT_ACCT
193 static inline int
194 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
195                         enum ip_conntrack_dir dir)
196 {
197         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
198         struct nfattr *nest_count = NFA_NEST(skb, type);
199         __be32 tmp;
200
201         tmp = htonl(ct->counters[dir].packets);
202         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
203
204         tmp = htonl(ct->counters[dir].bytes);
205         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
206
207         NFA_NEST_END(skb, nest_count);
208
209         return 0;
210
211 nfattr_failure:
212         return -1;
213 }
214 #else
215 #define ctnetlink_dump_counters(a, b, c) (0)
216 #endif
217
218 #ifdef CONFIG_NF_CONNTRACK_MARK
219 static inline int
220 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
221 {
222         __be32 mark = htonl(ct->mark);
223
224         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
225         return 0;
226
227 nfattr_failure:
228         return -1;
229 }
230 #else
231 #define ctnetlink_dump_mark(a, b) (0)
232 #endif
233
234 static inline int
235 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
236 {
237         __be32 id = htonl(ct->id);
238         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
239         return 0;
240
241 nfattr_failure:
242         return -1;
243 }
244
245 static inline int
246 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
247 {
248         __be32 use = htonl(atomic_read(&ct->ct_general.use));
249
250         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
251         return 0;
252
253 nfattr_failure:
254         return -1;
255 }
256
257 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
258
259 static int
260 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
261                     int event, int nowait,
262                     const struct nf_conn *ct)
263 {
264         struct nlmsghdr *nlh;
265         struct nfgenmsg *nfmsg;
266         struct nfattr *nest_parms;
267         unsigned char *b = skb_tail_pointer(skb);
268
269         event |= NFNL_SUBSYS_CTNETLINK << 8;
270         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
271         nfmsg  = NLMSG_DATA(nlh);
272
273         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
274         nfmsg->nfgen_family =
275                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
276         nfmsg->version      = NFNETLINK_V0;
277         nfmsg->res_id       = 0;
278
279         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
280         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
281                 goto nfattr_failure;
282         NFA_NEST_END(skb, nest_parms);
283
284         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
285         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
286                 goto nfattr_failure;
287         NFA_NEST_END(skb, nest_parms);
288
289         if (ctnetlink_dump_status(skb, ct) < 0 ||
290             ctnetlink_dump_timeout(skb, ct) < 0 ||
291             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
292             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
293             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
294             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
295             ctnetlink_dump_mark(skb, ct) < 0 ||
296             ctnetlink_dump_id(skb, ct) < 0 ||
297             ctnetlink_dump_use(skb, ct) < 0)
298                 goto nfattr_failure;
299
300         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
301         return skb->len;
302
303 nlmsg_failure:
304 nfattr_failure:
305         nlmsg_trim(skb, b);
306         return -1;
307 }
308
309 #ifdef CONFIG_NF_CONNTRACK_EVENTS
310 static int ctnetlink_conntrack_event(struct notifier_block *this,
311                                      unsigned long events, void *ptr)
312 {
313         struct nlmsghdr *nlh;
314         struct nfgenmsg *nfmsg;
315         struct nfattr *nest_parms;
316         struct nf_conn *ct = (struct nf_conn *)ptr;
317         struct sk_buff *skb;
318         unsigned int type;
319         sk_buff_data_t b;
320         unsigned int flags = 0, group;
321
322         /* ignore our fake conntrack entry */
323         if (ct == &nf_conntrack_untracked)
324                 return NOTIFY_DONE;
325
326         if (events & IPCT_DESTROY) {
327                 type = IPCTNL_MSG_CT_DELETE;
328                 group = NFNLGRP_CONNTRACK_DESTROY;
329         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
330                 type = IPCTNL_MSG_CT_NEW;
331                 flags = NLM_F_CREATE|NLM_F_EXCL;
332                 group = NFNLGRP_CONNTRACK_NEW;
333         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
334                 type = IPCTNL_MSG_CT_NEW;
335                 group = NFNLGRP_CONNTRACK_UPDATE;
336         } else
337                 return NOTIFY_DONE;
338
339         if (!nfnetlink_has_listeners(group))
340                 return NOTIFY_DONE;
341
342         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
343         if (!skb)
344                 return NOTIFY_DONE;
345
346         b = skb->tail;
347
348         type |= NFNL_SUBSYS_CTNETLINK << 8;
349         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
350         nfmsg = NLMSG_DATA(nlh);
351
352         nlh->nlmsg_flags    = flags;
353         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
354         nfmsg->version  = NFNETLINK_V0;
355         nfmsg->res_id   = 0;
356
357         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
358         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
359                 goto nfattr_failure;
360         NFA_NEST_END(skb, nest_parms);
361
362         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
363         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
364                 goto nfattr_failure;
365         NFA_NEST_END(skb, nest_parms);
366
367         if (events & IPCT_DESTROY) {
368                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
369                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
370                         goto nfattr_failure;
371         } else {
372                 if (ctnetlink_dump_status(skb, ct) < 0)
373                         goto nfattr_failure;
374
375                 if (ctnetlink_dump_timeout(skb, ct) < 0)
376                         goto nfattr_failure;
377
378                 if (events & IPCT_PROTOINFO
379                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
380                         goto nfattr_failure;
381
382                 if ((events & IPCT_HELPER || nfct_help(ct))
383                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
384                         goto nfattr_failure;
385
386 #ifdef CONFIG_NF_CONNTRACK_MARK
387                 if ((events & IPCT_MARK || ct->mark)
388                     && ctnetlink_dump_mark(skb, ct) < 0)
389                         goto nfattr_failure;
390 #endif
391
392                 if (events & IPCT_COUNTER_FILLING &&
393                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
394                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
395                         goto nfattr_failure;
396         }
397
398         nlh->nlmsg_len = skb->tail - b;
399         nfnetlink_send(skb, 0, group, 0);
400         return NOTIFY_DONE;
401
402 nlmsg_failure:
403 nfattr_failure:
404         kfree_skb(skb);
405         return NOTIFY_DONE;
406 }
407 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
408
409 static int ctnetlink_done(struct netlink_callback *cb)
410 {
411         if (cb->args[1])
412                 nf_ct_put((struct nf_conn *)cb->args[1]);
413         return 0;
414 }
415
416 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
417
418 static int
419 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
420 {
421         struct nf_conn *ct, *last;
422         struct nf_conntrack_tuple_hash *h;
423         struct list_head *i;
424         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
425         u_int8_t l3proto = nfmsg->nfgen_family;
426
427         read_lock_bh(&nf_conntrack_lock);
428         last = (struct nf_conn *)cb->args[1];
429         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
430 restart:
431                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
432                         h = (struct nf_conntrack_tuple_hash *) i;
433                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
434                                 continue;
435                         ct = nf_ct_tuplehash_to_ctrack(h);
436                         /* Dump entries of a given L3 protocol number.
437                          * If it is not specified, ie. l3proto == 0,
438                          * then dump everything. */
439                         if (l3proto && L3PROTO(ct) != l3proto)
440                                 continue;
441                         if (cb->args[1]) {
442                                 if (ct != last)
443                                         continue;
444                                 cb->args[1] = 0;
445                         }
446                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
447                                                 cb->nlh->nlmsg_seq,
448                                                 IPCTNL_MSG_CT_NEW,
449                                                 1, ct) < 0) {
450                                 nf_conntrack_get(&ct->ct_general);
451                                 cb->args[1] = (unsigned long)ct;
452                                 goto out;
453                         }
454 #ifdef CONFIG_NF_CT_ACCT
455                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
456                                                 IPCTNL_MSG_CT_GET_CTRZERO)
457                                 memset(&ct->counters, 0, sizeof(ct->counters));
458 #endif
459                 }
460                 if (cb->args[1]) {
461                         cb->args[1] = 0;
462                         goto restart;
463                 }
464         }
465 out:
466         read_unlock_bh(&nf_conntrack_lock);
467         if (last)
468                 nf_ct_put(last);
469
470         return skb->len;
471 }
472
473 static inline int
474 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
475 {
476         struct nfattr *tb[CTA_IP_MAX];
477         struct nf_conntrack_l3proto *l3proto;
478         int ret = 0;
479
480         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
481
482         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
483
484         if (likely(l3proto->nfattr_to_tuple))
485                 ret = l3proto->nfattr_to_tuple(tb, tuple);
486
487         nf_ct_l3proto_put(l3proto);
488
489         return ret;
490 }
491
492 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
493         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
494 };
495
496 static inline int
497 ctnetlink_parse_tuple_proto(struct nfattr *attr,
498                             struct nf_conntrack_tuple *tuple)
499 {
500         struct nfattr *tb[CTA_PROTO_MAX];
501         struct nf_conntrack_l4proto *l4proto;
502         int ret = 0;
503
504         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
505
506         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
507                 return -EINVAL;
508
509         if (!tb[CTA_PROTO_NUM-1])
510                 return -EINVAL;
511         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
512
513         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
514
515         if (likely(l4proto->nfattr_to_tuple))
516                 ret = l4proto->nfattr_to_tuple(tb, tuple);
517
518         nf_ct_l4proto_put(l4proto);
519
520         return ret;
521 }
522
523 static inline int
524 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
525                       enum ctattr_tuple type, u_int8_t l3num)
526 {
527         struct nfattr *tb[CTA_TUPLE_MAX];
528         int err;
529
530         memset(tuple, 0, sizeof(*tuple));
531
532         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
533
534         if (!tb[CTA_TUPLE_IP-1])
535                 return -EINVAL;
536
537         tuple->src.l3num = l3num;
538
539         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
540         if (err < 0)
541                 return err;
542
543         if (!tb[CTA_TUPLE_PROTO-1])
544                 return -EINVAL;
545
546         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
547         if (err < 0)
548                 return err;
549
550         /* orig and expect tuples get DIR_ORIGINAL */
551         if (type == CTA_TUPLE_REPLY)
552                 tuple->dst.dir = IP_CT_DIR_REPLY;
553         else
554                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
555
556         return 0;
557 }
558
559 #ifdef CONFIG_NF_NAT_NEEDED
560 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
561         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
562         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
563 };
564
565 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
566                                      const struct nf_conn *ct,
567                                      struct nf_nat_range *range)
568 {
569         struct nfattr *tb[CTA_PROTONAT_MAX];
570         struct nf_nat_protocol *npt;
571
572         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
573
574         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
575                 return -EINVAL;
576
577         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
578
579         if (!npt->nfattr_to_range) {
580                 nf_nat_proto_put(npt);
581                 return 0;
582         }
583
584         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
585         if (npt->nfattr_to_range(tb, range) > 0)
586                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
587
588         nf_nat_proto_put(npt);
589
590         return 0;
591 }
592
593 static const size_t cta_min_nat[CTA_NAT_MAX] = {
594         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
595         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
596 };
597
598 static inline int
599 nfnetlink_parse_nat(struct nfattr *nat,
600                     const struct nf_conn *ct, struct nf_nat_range *range)
601 {
602         struct nfattr *tb[CTA_NAT_MAX];
603         int err;
604
605         memset(range, 0, sizeof(*range));
606
607         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
608
609         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
610                 return -EINVAL;
611
612         if (tb[CTA_NAT_MINIP-1])
613                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
614
615         if (!tb[CTA_NAT_MAXIP-1])
616                 range->max_ip = range->min_ip;
617         else
618                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
619
620         if (range->min_ip)
621                 range->flags |= IP_NAT_RANGE_MAP_IPS;
622
623         if (!tb[CTA_NAT_PROTO-1])
624                 return 0;
625
626         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
627         if (err < 0)
628                 return err;
629
630         return 0;
631 }
632 #endif
633
634 static inline int
635 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
636 {
637         struct nfattr *tb[CTA_HELP_MAX];
638
639         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
640
641         if (!tb[CTA_HELP_NAME-1])
642                 return -EINVAL;
643
644         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
645
646         return 0;
647 }
648
649 static const size_t cta_min[CTA_MAX] = {
650         [CTA_STATUS-1]          = sizeof(u_int32_t),
651         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
652         [CTA_MARK-1]            = sizeof(u_int32_t),
653         [CTA_USE-1]             = sizeof(u_int32_t),
654         [CTA_ID-1]              = sizeof(u_int32_t)
655 };
656
657 static int
658 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
659                         struct nlmsghdr *nlh, struct nfattr *cda[])
660 {
661         struct nf_conntrack_tuple_hash *h;
662         struct nf_conntrack_tuple tuple;
663         struct nf_conn *ct;
664         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
665         u_int8_t u3 = nfmsg->nfgen_family;
666         int err = 0;
667
668         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
669                 return -EINVAL;
670
671         if (cda[CTA_TUPLE_ORIG-1])
672                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
673         else if (cda[CTA_TUPLE_REPLY-1])
674                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
675         else {
676                 /* Flush the whole table */
677                 nf_conntrack_flush();
678                 return 0;
679         }
680
681         if (err < 0)
682                 return err;
683
684         h = nf_conntrack_find_get(&tuple, NULL);
685         if (!h)
686                 return -ENOENT;
687
688         ct = nf_ct_tuplehash_to_ctrack(h);
689
690         if (cda[CTA_ID-1]) {
691                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
692                 if (ct->id != id) {
693                         nf_ct_put(ct);
694                         return -ENOENT;
695                 }
696         }
697         if (del_timer(&ct->timeout))
698                 ct->timeout.function((unsigned long)ct);
699
700         nf_ct_put(ct);
701
702         return 0;
703 }
704
705 static int
706 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
707                         struct nlmsghdr *nlh, struct nfattr *cda[])
708 {
709         struct nf_conntrack_tuple_hash *h;
710         struct nf_conntrack_tuple tuple;
711         struct nf_conn *ct;
712         struct sk_buff *skb2 = NULL;
713         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
714         u_int8_t u3 = nfmsg->nfgen_family;
715         int err = 0;
716
717         if (nlh->nlmsg_flags & NLM_F_DUMP) {
718 #ifndef CONFIG_NF_CT_ACCT
719                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
720                         return -ENOTSUPP;
721 #endif
722                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
723                                           ctnetlink_done);
724         }
725
726         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
727                 return -EINVAL;
728
729         if (cda[CTA_TUPLE_ORIG-1])
730                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
731         else if (cda[CTA_TUPLE_REPLY-1])
732                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
733         else
734                 return -EINVAL;
735
736         if (err < 0)
737                 return err;
738
739         h = nf_conntrack_find_get(&tuple, NULL);
740         if (!h)
741                 return -ENOENT;
742
743         ct = nf_ct_tuplehash_to_ctrack(h);
744
745         err = -ENOMEM;
746         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
747         if (!skb2) {
748                 nf_ct_put(ct);
749                 return -ENOMEM;
750         }
751
752         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
753                                   IPCTNL_MSG_CT_NEW, 1, ct);
754         nf_ct_put(ct);
755         if (err <= 0)
756                 goto free;
757
758         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
759         if (err < 0)
760                 goto out;
761
762         return 0;
763
764 free:
765         kfree_skb(skb2);
766 out:
767         return err;
768 }
769
770 static inline int
771 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
772 {
773         unsigned long d;
774         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
775         d = ct->status ^ status;
776
777         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
778                 /* unchangeable */
779                 return -EINVAL;
780
781         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
782                 /* SEEN_REPLY bit can only be set */
783                 return -EINVAL;
784
785
786         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
787                 /* ASSURED bit can only be set */
788                 return -EINVAL;
789
790         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
791 #ifndef CONFIG_NF_NAT_NEEDED
792                 return -EINVAL;
793 #else
794                 struct nf_nat_range range;
795
796                 if (cda[CTA_NAT_DST-1]) {
797                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
798                                                 &range) < 0)
799                                 return -EINVAL;
800                         if (nf_nat_initialized(ct,
801                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
802                                 return -EEXIST;
803                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
804                 }
805                 if (cda[CTA_NAT_SRC-1]) {
806                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
807                                                 &range) < 0)
808                                 return -EINVAL;
809                         if (nf_nat_initialized(ct,
810                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
811                                 return -EEXIST;
812                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
813                 }
814 #endif
815         }
816
817         /* Be careful here, modifying NAT bits can screw up things,
818          * so don't let users modify them directly if they don't pass
819          * nf_nat_range. */
820         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
821         return 0;
822 }
823
824
825 static inline int
826 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
827 {
828         struct nf_conntrack_helper *helper;
829         struct nf_conn_help *help = nfct_help(ct);
830         char *helpname;
831         int err;
832
833         /* don't change helper of sibling connections */
834         if (ct->master)
835                 return -EINVAL;
836
837         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
838         if (err < 0)
839                 return err;
840
841         if (!strcmp(helpname, "")) {
842                 if (help && help->helper) {
843                         /* we had a helper before ... */
844                         nf_ct_remove_expectations(ct);
845                         help->helper = NULL;
846                 }
847
848                 return 0;
849         }
850
851         if (!help) {
852                 /* FIXME: we need to reallocate and rehash */
853                 return -EBUSY;
854         }
855
856         helper = __nf_conntrack_helper_find_byname(helpname);
857         if (helper == NULL)
858                 return -EINVAL;
859
860         if (help->helper == helper)
861                 return 0;
862
863         if (help->helper)
864                 /* we had a helper before ... */
865                 nf_ct_remove_expectations(ct);
866
867         /* need to zero data of old helper */
868         memset(&help->help, 0, sizeof(help->help));
869         help->helper = helper;
870
871         return 0;
872 }
873
874 static inline int
875 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
876 {
877         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
878
879         if (!del_timer(&ct->timeout))
880                 return -ETIME;
881
882         ct->timeout.expires = jiffies + timeout * HZ;
883         add_timer(&ct->timeout);
884
885         return 0;
886 }
887
888 static inline int
889 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
890 {
891         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
892         struct nf_conntrack_l4proto *l4proto;
893         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
894         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
895         int err = 0;
896
897         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
898
899         l4proto = nf_ct_l4proto_find_get(l3num, npt);
900
901         if (l4proto->from_nfattr)
902                 err = l4proto->from_nfattr(tb, ct);
903         nf_ct_l4proto_put(l4proto);
904
905         return err;
906 }
907
908 static int
909 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
910 {
911         int err;
912
913         if (cda[CTA_HELP-1]) {
914                 err = ctnetlink_change_helper(ct, cda);
915                 if (err < 0)
916                         return err;
917         }
918
919         if (cda[CTA_TIMEOUT-1]) {
920                 err = ctnetlink_change_timeout(ct, cda);
921                 if (err < 0)
922                         return err;
923         }
924
925         if (cda[CTA_STATUS-1]) {
926                 err = ctnetlink_change_status(ct, cda);
927                 if (err < 0)
928                         return err;
929         }
930
931         if (cda[CTA_PROTOINFO-1]) {
932                 err = ctnetlink_change_protoinfo(ct, cda);
933                 if (err < 0)
934                         return err;
935         }
936
937 #if defined(CONFIG_NF_CONNTRACK_MARK)
938         if (cda[CTA_MARK-1])
939                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
940 #endif
941
942         return 0;
943 }
944
945 static int
946 ctnetlink_create_conntrack(struct nfattr *cda[],
947                            struct nf_conntrack_tuple *otuple,
948                            struct nf_conntrack_tuple *rtuple)
949 {
950         struct nf_conn *ct;
951         int err = -EINVAL;
952         struct nf_conn_help *help;
953
954         ct = nf_conntrack_alloc(otuple, rtuple);
955         if (ct == NULL || IS_ERR(ct))
956                 return -ENOMEM;
957
958         if (!cda[CTA_TIMEOUT-1])
959                 goto err;
960         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
961
962         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
963         ct->status |= IPS_CONFIRMED;
964
965         if (cda[CTA_STATUS-1]) {
966                 err = ctnetlink_change_status(ct, cda);
967                 if (err < 0)
968                         goto err;
969         }
970
971         if (cda[CTA_PROTOINFO-1]) {
972                 err = ctnetlink_change_protoinfo(ct, cda);
973                 if (err < 0)
974                         goto err;
975         }
976
977 #if defined(CONFIG_NF_CONNTRACK_MARK)
978         if (cda[CTA_MARK-1])
979                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
980 #endif
981
982         help = nfct_help(ct);
983         if (help)
984                 help->helper = nf_ct_helper_find_get(rtuple);
985
986         add_timer(&ct->timeout);
987         nf_conntrack_hash_insert(ct);
988
989         if (help && help->helper)
990                 nf_ct_helper_put(help->helper);
991
992         return 0;
993
994 err:
995         nf_conntrack_free(ct);
996         return err;
997 }
998
999 static int
1000 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1001                         struct nlmsghdr *nlh, struct nfattr *cda[])
1002 {
1003         struct nf_conntrack_tuple otuple, rtuple;
1004         struct nf_conntrack_tuple_hash *h = NULL;
1005         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1006         u_int8_t u3 = nfmsg->nfgen_family;
1007         int err = 0;
1008
1009         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1010                 return -EINVAL;
1011
1012         if (cda[CTA_TUPLE_ORIG-1]) {
1013                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1014                 if (err < 0)
1015                         return err;
1016         }
1017
1018         if (cda[CTA_TUPLE_REPLY-1]) {
1019                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1020                 if (err < 0)
1021                         return err;
1022         }
1023
1024         write_lock_bh(&nf_conntrack_lock);
1025         if (cda[CTA_TUPLE_ORIG-1])
1026                 h = __nf_conntrack_find(&otuple, NULL);
1027         else if (cda[CTA_TUPLE_REPLY-1])
1028                 h = __nf_conntrack_find(&rtuple, NULL);
1029
1030         if (h == NULL) {
1031                 write_unlock_bh(&nf_conntrack_lock);
1032                 err = -ENOENT;
1033                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1034                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1035                 return err;
1036         }
1037         /* implicit 'else' */
1038
1039         /* we only allow nat config for new conntracks */
1040         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1041                 err = -EINVAL;
1042                 goto out_unlock;
1043         }
1044
1045         /* We manipulate the conntrack inside the global conntrack table lock,
1046          * so there's no need to increase the refcount */
1047         err = -EEXIST;
1048         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1049                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1050
1051 out_unlock:
1052         write_unlock_bh(&nf_conntrack_lock);
1053         return err;
1054 }
1055
1056 /***********************************************************************
1057  * EXPECT
1058  ***********************************************************************/
1059
1060 static inline int
1061 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1062                          const struct nf_conntrack_tuple *tuple,
1063                          enum ctattr_expect type)
1064 {
1065         struct nfattr *nest_parms = NFA_NEST(skb, type);
1066
1067         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1068                 goto nfattr_failure;
1069
1070         NFA_NEST_END(skb, nest_parms);
1071
1072         return 0;
1073
1074 nfattr_failure:
1075         return -1;
1076 }
1077
1078 static inline int
1079 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1080                         const struct nf_conntrack_tuple *tuple,
1081                         const struct nf_conntrack_tuple *mask)
1082 {
1083         int ret;
1084         struct nf_conntrack_l3proto *l3proto;
1085         struct nf_conntrack_l4proto *l4proto;
1086         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1087
1088         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1089         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1090         nf_ct_l3proto_put(l3proto);
1091
1092         if (unlikely(ret < 0))
1093                 goto nfattr_failure;
1094
1095         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1096         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1097         nf_ct_l4proto_put(l4proto);
1098         if (unlikely(ret < 0))
1099                 goto nfattr_failure;
1100
1101         NFA_NEST_END(skb, nest_parms);
1102
1103         return 0;
1104
1105 nfattr_failure:
1106         return -1;
1107 }
1108
1109 static inline int
1110 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1111                           const struct nf_conntrack_expect *exp)
1112 {
1113         struct nf_conn *master = exp->master;
1114         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1115         __be32 id = htonl(exp->id);
1116
1117         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1118                 goto nfattr_failure;
1119         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1120                 goto nfattr_failure;
1121         if (ctnetlink_exp_dump_tuple(skb,
1122                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1123                                  CTA_EXPECT_MASTER) < 0)
1124                 goto nfattr_failure;
1125
1126         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1127         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1128
1129         return 0;
1130
1131 nfattr_failure:
1132         return -1;
1133 }
1134
1135 static int
1136 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1137                     int event,
1138                     int nowait,
1139                     const struct nf_conntrack_expect *exp)
1140 {
1141         struct nlmsghdr *nlh;
1142         struct nfgenmsg *nfmsg;
1143         unsigned char *b = skb_tail_pointer(skb);
1144
1145         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1146         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1147         nfmsg  = NLMSG_DATA(nlh);
1148
1149         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1150         nfmsg->nfgen_family = exp->tuple.src.l3num;
1151         nfmsg->version      = NFNETLINK_V0;
1152         nfmsg->res_id       = 0;
1153
1154         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1155                 goto nfattr_failure;
1156
1157         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1158         return skb->len;
1159
1160 nlmsg_failure:
1161 nfattr_failure:
1162         nlmsg_trim(skb, b);
1163         return -1;
1164 }
1165
1166 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1167 static int ctnetlink_expect_event(struct notifier_block *this,
1168                                   unsigned long events, void *ptr)
1169 {
1170         struct nlmsghdr *nlh;
1171         struct nfgenmsg *nfmsg;
1172         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1173         struct sk_buff *skb;
1174         unsigned int type;
1175         sk_buff_data_t b;
1176         int flags = 0;
1177
1178         if (events & IPEXP_NEW) {
1179                 type = IPCTNL_MSG_EXP_NEW;
1180                 flags = NLM_F_CREATE|NLM_F_EXCL;
1181         } else
1182                 return NOTIFY_DONE;
1183
1184         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1185                 return NOTIFY_DONE;
1186
1187         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1188         if (!skb)
1189                 return NOTIFY_DONE;
1190
1191         b = skb->tail;
1192
1193         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1194         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1195         nfmsg = NLMSG_DATA(nlh);
1196
1197         nlh->nlmsg_flags    = flags;
1198         nfmsg->nfgen_family = exp->tuple.src.l3num;
1199         nfmsg->version      = NFNETLINK_V0;
1200         nfmsg->res_id       = 0;
1201
1202         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1203                 goto nfattr_failure;
1204
1205         nlh->nlmsg_len = skb->tail - b;
1206         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1207         return NOTIFY_DONE;
1208
1209 nlmsg_failure:
1210 nfattr_failure:
1211         kfree_skb(skb);
1212         return NOTIFY_DONE;
1213 }
1214 #endif
1215
1216 static int
1217 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1218 {
1219         struct nf_conntrack_expect *exp = NULL;
1220         struct list_head *i;
1221         u_int32_t *id = (u_int32_t *) &cb->args[0];
1222         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1223         u_int8_t l3proto = nfmsg->nfgen_family;
1224
1225         read_lock_bh(&nf_conntrack_lock);
1226         list_for_each_prev(i, &nf_conntrack_expect_list) {
1227                 exp = (struct nf_conntrack_expect *) i;
1228                 if (l3proto && exp->tuple.src.l3num != l3proto)
1229                         continue;
1230                 if (exp->id <= *id)
1231                         continue;
1232                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1233                                             cb->nlh->nlmsg_seq,
1234                                             IPCTNL_MSG_EXP_NEW,
1235                                             1, exp) < 0)
1236                         goto out;
1237                 *id = exp->id;
1238         }
1239 out:
1240         read_unlock_bh(&nf_conntrack_lock);
1241
1242         return skb->len;
1243 }
1244
1245 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1246         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1247         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1248 };
1249
1250 static int
1251 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1252                      struct nlmsghdr *nlh, struct nfattr *cda[])
1253 {
1254         struct nf_conntrack_tuple tuple;
1255         struct nf_conntrack_expect *exp;
1256         struct sk_buff *skb2;
1257         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1258         u_int8_t u3 = nfmsg->nfgen_family;
1259         int err = 0;
1260
1261         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1262                 return -EINVAL;
1263
1264         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1265                 return netlink_dump_start(ctnl, skb, nlh,
1266                                           ctnetlink_exp_dump_table,
1267                                           ctnetlink_done);
1268         }
1269
1270         if (cda[CTA_EXPECT_MASTER-1])
1271                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1272         else
1273                 return -EINVAL;
1274
1275         if (err < 0)
1276                 return err;
1277
1278         exp = nf_conntrack_expect_find_get(&tuple);
1279         if (!exp)
1280                 return -ENOENT;
1281
1282         if (cda[CTA_EXPECT_ID-1]) {
1283                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1284                 if (exp->id != ntohl(id)) {
1285                         nf_conntrack_expect_put(exp);
1286                         return -ENOENT;
1287                 }
1288         }
1289
1290         err = -ENOMEM;
1291         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1292         if (!skb2)
1293                 goto out;
1294
1295         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1296                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1297                                       1, exp);
1298         if (err <= 0)
1299                 goto free;
1300
1301         nf_conntrack_expect_put(exp);
1302
1303         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1304
1305 free:
1306         kfree_skb(skb2);
1307 out:
1308         nf_conntrack_expect_put(exp);
1309         return err;
1310 }
1311
1312 static int
1313 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1314                      struct nlmsghdr *nlh, struct nfattr *cda[])
1315 {
1316         struct nf_conntrack_expect *exp, *tmp;
1317         struct nf_conntrack_tuple tuple;
1318         struct nf_conntrack_helper *h;
1319         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1320         u_int8_t u3 = nfmsg->nfgen_family;
1321         int err;
1322
1323         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1324                 return -EINVAL;
1325
1326         if (cda[CTA_EXPECT_TUPLE-1]) {
1327                 /* delete a single expect by tuple */
1328                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1329                 if (err < 0)
1330                         return err;
1331
1332                 /* bump usage count to 2 */
1333                 exp = nf_conntrack_expect_find_get(&tuple);
1334                 if (!exp)
1335                         return -ENOENT;
1336
1337                 if (cda[CTA_EXPECT_ID-1]) {
1338                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1339                         if (exp->id != ntohl(id)) {
1340                                 nf_conntrack_expect_put(exp);
1341                                 return -ENOENT;
1342                         }
1343                 }
1344
1345                 /* after list removal, usage count == 1 */
1346                 nf_conntrack_unexpect_related(exp);
1347                 /* have to put what we 'get' above.
1348                  * after this line usage count == 0 */
1349                 nf_conntrack_expect_put(exp);
1350         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1351                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1352
1353                 /* delete all expectations for this helper */
1354                 write_lock_bh(&nf_conntrack_lock);
1355                 h = __nf_conntrack_helper_find_byname(name);
1356                 if (!h) {
1357                         write_unlock_bh(&nf_conntrack_lock);
1358                         return -EINVAL;
1359                 }
1360                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1361                                          list) {
1362                         struct nf_conn_help *m_help = nfct_help(exp->master);
1363                         if (m_help->helper == h
1364                             && del_timer(&exp->timeout)) {
1365                                 nf_ct_unlink_expect(exp);
1366                                 nf_conntrack_expect_put(exp);
1367                         }
1368                 }
1369                 write_unlock_bh(&nf_conntrack_lock);
1370         } else {
1371                 /* This basically means we have to flush everything*/
1372                 write_lock_bh(&nf_conntrack_lock);
1373                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1374                                          list) {
1375                         if (del_timer(&exp->timeout)) {
1376                                 nf_ct_unlink_expect(exp);
1377                                 nf_conntrack_expect_put(exp);
1378                         }
1379                 }
1380                 write_unlock_bh(&nf_conntrack_lock);
1381         }
1382
1383         return 0;
1384 }
1385 static int
1386 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1387 {
1388         return -EOPNOTSUPP;
1389 }
1390
1391 static int
1392 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1393 {
1394         struct nf_conntrack_tuple tuple, mask, master_tuple;
1395         struct nf_conntrack_tuple_hash *h = NULL;
1396         struct nf_conntrack_expect *exp;
1397         struct nf_conn *ct;
1398         struct nf_conn_help *help;
1399         int err = 0;
1400
1401         /* caller guarantees that those three CTA_EXPECT_* exist */
1402         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1403         if (err < 0)
1404                 return err;
1405         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1406         if (err < 0)
1407                 return err;
1408         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1409         if (err < 0)
1410                 return err;
1411
1412         /* Look for master conntrack of this expectation */
1413         h = nf_conntrack_find_get(&master_tuple, NULL);
1414         if (!h)
1415                 return -ENOENT;
1416         ct = nf_ct_tuplehash_to_ctrack(h);
1417         help = nfct_help(ct);
1418
1419         if (!help || !help->helper) {
1420                 /* such conntrack hasn't got any helper, abort */
1421                 err = -EINVAL;
1422                 goto out;
1423         }
1424
1425         exp = nf_conntrack_expect_alloc(ct);
1426         if (!exp) {
1427                 err = -ENOMEM;
1428                 goto out;
1429         }
1430
1431         exp->expectfn = NULL;
1432         exp->flags = 0;
1433         exp->master = ct;
1434         exp->helper = NULL;
1435         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1436         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1437
1438         err = nf_conntrack_expect_related(exp);
1439         nf_conntrack_expect_put(exp);
1440
1441 out:
1442         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1443         return err;
1444 }
1445
1446 static int
1447 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1448                      struct nlmsghdr *nlh, struct nfattr *cda[])
1449 {
1450         struct nf_conntrack_tuple tuple;
1451         struct nf_conntrack_expect *exp;
1452         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1453         u_int8_t u3 = nfmsg->nfgen_family;
1454         int err = 0;
1455
1456         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1457                 return -EINVAL;
1458
1459         if (!cda[CTA_EXPECT_TUPLE-1]
1460             || !cda[CTA_EXPECT_MASK-1]
1461             || !cda[CTA_EXPECT_MASTER-1])
1462                 return -EINVAL;
1463
1464         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1465         if (err < 0)
1466                 return err;
1467
1468         write_lock_bh(&nf_conntrack_lock);
1469         exp = __nf_conntrack_expect_find(&tuple);
1470
1471         if (!exp) {
1472                 write_unlock_bh(&nf_conntrack_lock);
1473                 err = -ENOENT;
1474                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1475                         err = ctnetlink_create_expect(cda, u3);
1476                 return err;
1477         }
1478
1479         err = -EEXIST;
1480         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1481                 err = ctnetlink_change_expect(exp, cda);
1482         write_unlock_bh(&nf_conntrack_lock);
1483
1484         return err;
1485 }
1486
1487 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1488 static struct notifier_block ctnl_notifier = {
1489         .notifier_call  = ctnetlink_conntrack_event,
1490 };
1491
1492 static struct notifier_block ctnl_notifier_exp = {
1493         .notifier_call  = ctnetlink_expect_event,
1494 };
1495 #endif
1496
1497 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1498         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1499                                             .attr_count = CTA_MAX, },
1500         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1501                                             .attr_count = CTA_MAX, },
1502         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1503                                             .attr_count = CTA_MAX, },
1504         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1505                                             .attr_count = CTA_MAX, },
1506 };
1507
1508 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1509         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1510                                             .attr_count = CTA_EXPECT_MAX, },
1511         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1512                                             .attr_count = CTA_EXPECT_MAX, },
1513         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1514                                             .attr_count = CTA_EXPECT_MAX, },
1515 };
1516
1517 static struct nfnetlink_subsystem ctnl_subsys = {
1518         .name                           = "conntrack",
1519         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1520         .cb_count                       = IPCTNL_MSG_MAX,
1521         .cb                             = ctnl_cb,
1522 };
1523
1524 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1525         .name                           = "conntrack_expect",
1526         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1527         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1528         .cb                             = ctnl_exp_cb,
1529 };
1530
1531 MODULE_ALIAS("ip_conntrack_netlink");
1532 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1533 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1534
1535 static int __init ctnetlink_init(void)
1536 {
1537         int ret;
1538
1539         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1540         ret = nfnetlink_subsys_register(&ctnl_subsys);
1541         if (ret < 0) {
1542                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1543                 goto err_out;
1544         }
1545
1546         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1547         if (ret < 0) {
1548                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1549                 goto err_unreg_subsys;
1550         }
1551
1552 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1553         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1554         if (ret < 0) {
1555                 printk("ctnetlink_init: cannot register notifier.\n");
1556                 goto err_unreg_exp_subsys;
1557         }
1558
1559         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1560         if (ret < 0) {
1561                 printk("ctnetlink_init: cannot expect register notifier.\n");
1562                 goto err_unreg_notifier;
1563         }
1564 #endif
1565
1566         return 0;
1567
1568 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1569 err_unreg_notifier:
1570         nf_conntrack_unregister_notifier(&ctnl_notifier);
1571 err_unreg_exp_subsys:
1572         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1573 #endif
1574 err_unreg_subsys:
1575         nfnetlink_subsys_unregister(&ctnl_subsys);
1576 err_out:
1577         return ret;
1578 }
1579
1580 static void __exit ctnetlink_exit(void)
1581 {
1582         printk("ctnetlink: unregistering from nfnetlink.\n");
1583
1584 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1585         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1586         nf_conntrack_unregister_notifier(&ctnl_notifier);
1587 #endif
1588
1589         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1590         nfnetlink_subsys_unregister(&ctnl_subsys);
1591         return;
1592 }
1593
1594 module_init(ctnetlink_init);
1595 module_exit(ctnetlink_exit);