Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
[deliverable/linux.git] / net / netfilter / xt_CT.c
CommitLineData
84f3bb9a
PM
1/*
2 * Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
a7fed762 8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
84f3bb9a 9#include <linux/module.h>
5a0e3ad6 10#include <linux/gfp.h>
84f3bb9a 11#include <linux/skbuff.h>
84f3bb9a
PM
12#include <linux/netfilter_ipv4/ip_tables.h>
13#include <linux/netfilter_ipv6/ip6_tables.h>
14#include <linux/netfilter/x_tables.h>
15#include <linux/netfilter/xt_CT.h>
16#include <net/netfilter/nf_conntrack.h>
eeb4cb95 17#include <net/netfilter/nf_conntrack_l4proto.h>
84f3bb9a
PM
18#include <net/netfilter/nf_conntrack_helper.h>
19#include <net/netfilter/nf_conntrack_ecache.h>
24de58f4 20#include <net/netfilter/nf_conntrack_timeout.h>
5d0aa2cc 21#include <net/netfilter/nf_conntrack_zones.h>
84f3bb9a 22
d52ed437 23static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
84f3bb9a 24{
84f3bb9a
PM
25 /* Previously seen (loopback)? Ignore. */
26 if (skb->nfct != NULL)
27 return XT_CONTINUE;
28
27e7190e
ED
29 /* special case the untracked ct : we want the percpu object */
30 if (!ct)
31 ct = nf_ct_untracked_get();
84f3bb9a
PM
32 atomic_inc(&ct->ct_general.use);
33 skb->nfct = &ct->ct_general;
34 skb->nfctinfo = IP_CT_NEW;
35
36 return XT_CONTINUE;
37}
38
d52ed437 39static unsigned int xt_ct_target_v0(struct sk_buff *skb,
24de58f4
PNA
40 const struct xt_action_param *par)
41{
d52ed437 42 const struct xt_ct_target_info *info = par->targinfo;
24de58f4
PNA
43 struct nf_conn *ct = info->ct;
44
d52ed437
PNA
45 return xt_ct_target(skb, ct);
46}
24de58f4 47
d52ed437
PNA
48static unsigned int xt_ct_target_v1(struct sk_buff *skb,
49 const struct xt_action_param *par)
50{
51 const struct xt_ct_target_info_v1 *info = par->targinfo;
52 struct nf_conn *ct = info->ct;
24de58f4 53
d52ed437 54 return xt_ct_target(skb, ct);
24de58f4
PNA
55}
56
84f3bb9a
PM
57static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
58{
076f7839 59 if (par->family == NFPROTO_IPV4) {
84f3bb9a
PM
60 const struct ipt_entry *e = par->entryinfo;
61
62 if (e->ip.invflags & IPT_INV_PROTO)
63 return 0;
64 return e->ip.proto;
076f7839 65 } else if (par->family == NFPROTO_IPV6) {
84f3bb9a
PM
66 const struct ip6t_entry *e = par->entryinfo;
67
68 if (e->ipv6.invflags & IP6T_INV_PROTO)
69 return 0;
70 return e->ipv6.proto;
71 } else
72 return 0;
73}
74
236df005
PNA
75static int
76xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
77 const struct xt_tgchk_param *par)
78{
79 struct nf_conntrack_helper *helper;
80 struct nf_conn_help *help;
81 u8 proto;
82
83 proto = xt_ct_find_proto(par);
84 if (!proto) {
85 pr_info("You must specify a L4 protocol, and not use "
86 "inversions on it.\n");
87 return -ENOENT;
88 }
89
90 helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
91 proto);
92 if (helper == NULL) {
93 pr_info("No such helper \"%s\"\n", helper_name);
94 return -ENOENT;
95 }
96
97 help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
98 if (help == NULL) {
99 module_put(helper->me);
100 return -ENOMEM;
101 }
102
103 help->helper = helper;
104 return 0;
105}
106
ee14186f
PNA
107#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
108static void __xt_ct_tg_timeout_put(struct ctnl_timeout *timeout)
109{
110 typeof(nf_ct_timeout_put_hook) timeout_put;
111
112 timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
113 if (timeout_put)
114 timeout_put(timeout);
115}
116#endif
117
236df005
PNA
118static int
119xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
120 const char *timeout_name)
121{
122#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
123 typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
124 struct ctnl_timeout *timeout;
125 struct nf_conn_timeout *timeout_ext;
236df005
PNA
126 struct nf_conntrack_l4proto *l4proto;
127 int ret = 0;
0153d5a8 128 u8 proto;
236df005
PNA
129
130 rcu_read_lock();
131 timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
132 if (timeout_find_get == NULL) {
133 ret = -ENOENT;
134 pr_info("Timeout policy base is empty\n");
135 goto out;
136 }
137
0153d5a8
PNA
138 proto = xt_ct_find_proto(par);
139 if (!proto) {
236df005 140 ret = -EINVAL;
0153d5a8
PNA
141 pr_info("You must specify a L4 protocol, and not use "
142 "inversions on it.\n");
236df005
PNA
143 goto out;
144 }
145
146 timeout = timeout_find_get(timeout_name);
147 if (timeout == NULL) {
148 ret = -ENOENT;
149 pr_info("No such timeout policy \"%s\"\n", timeout_name);
150 goto out;
151 }
152
153 if (timeout->l3num != par->family) {
154 ret = -EINVAL;
155 pr_info("Timeout policy `%s' can only be used by L3 protocol "
156 "number %d\n", timeout_name, timeout->l3num);
157 goto err_put_timeout;
158 }
159 /* Make sure the timeout policy matches any existing protocol tracker,
160 * otherwise default to generic.
161 */
0153d5a8 162 l4proto = __nf_ct_l4proto_find(par->family, proto);
236df005
PNA
163 if (timeout->l4proto->l4proto != l4proto->l4proto) {
164 ret = -EINVAL;
165 pr_info("Timeout policy `%s' can only be used by L4 protocol "
166 "number %d\n",
167 timeout_name, timeout->l4proto->l4proto);
168 goto err_put_timeout;
169 }
170 timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
171 if (timeout_ext == NULL)
172 ret = -ENOMEM;
173
174err_put_timeout:
175 __xt_ct_tg_timeout_put(timeout);
176out:
177 rcu_read_unlock();
178 return ret;
179#else
180 return -EOPNOTSUPP;
181#endif
182}
183
d52ed437
PNA
184static int xt_ct_tg_check(const struct xt_tgchk_param *par,
185 struct xt_ct_target_info_v1 *info)
24de58f4 186{
24de58f4 187 struct nf_conntrack_tuple t;
24de58f4 188 struct nf_conn *ct;
4610476d 189 int ret = -EOPNOTSUPP;
236df005 190
24de58f4 191 if (info->flags & XT_CT_NOTRACK) {
27e7190e 192 ct = NULL;
24de58f4
PNA
193 goto out;
194 }
195
196#ifndef CONFIG_NF_CONNTRACK_ZONES
197 if (info->zone)
198 goto err1;
199#endif
200
201 ret = nf_ct_l3proto_try_module_get(par->family);
202 if (ret < 0)
203 goto err1;
204
205 memset(&t, 0, sizeof(t));
206 ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
207 ret = PTR_ERR(ct);
208 if (IS_ERR(ct))
209 goto err2;
210
211 ret = 0;
212 if ((info->ct_events || info->exp_events) &&
213 !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
214 GFP_KERNEL))
215 goto err3;
216
217 if (info->helper[0]) {
236df005
PNA
218 ret = xt_ct_set_helper(ct, info->helper, par);
219 if (ret < 0)
1afc5679 220 goto err3;
24de58f4
PNA
221 }
222
6cf51852 223 if (info->timeout[0]) {
236df005
PNA
224 ret = xt_ct_set_timeout(ct, par, info->timeout);
225 if (ret < 0)
226 goto err3;
24de58f4 227 }
24de58f4
PNA
228
229 __set_bit(IPS_TEMPLATE_BIT, &ct->status);
230 __set_bit(IPS_CONFIRMED_BIT, &ct->status);
252b3e8c
PNA
231
232 /* Overload tuple linked list to put us in template list. */
233 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
234 &par->net->ct.tmpl);
24de58f4
PNA
235out:
236 info->ct = ct;
237 return 0;
238
239err3:
240 nf_conntrack_free(ct);
241err2:
242 nf_ct_l3proto_module_put(par->family);
243err1:
244 return ret;
245}
246
d52ed437 247static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
84f3bb9a
PM
248{
249 struct xt_ct_target_info *info = par->targinfo;
d52ed437
PNA
250 struct xt_ct_target_info_v1 info_v1 = {
251 .flags = info->flags,
252 .zone = info->zone,
253 .ct_events = info->ct_events,
254 .exp_events = info->exp_events,
255 };
256 int ret;
84f3bb9a 257
5474f57f
PNA
258 if (info->flags & ~XT_CT_NOTRACK)
259 return -EINVAL;
260
d52ed437 261 memcpy(info_v1.helper, info->helper, sizeof(info->helper));
84f3bb9a 262
d52ed437
PNA
263 ret = xt_ct_tg_check(par, &info_v1);
264 if (ret < 0)
265 return ret;
266
267 info->ct = info_v1.ct;
268
269 return ret;
270}
271
272static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
273{
5474f57f
PNA
274 struct xt_ct_target_info_v1 *info = par->targinfo;
275
276 if (info->flags & ~XT_CT_NOTRACK)
277 return -EINVAL;
278
279 return xt_ct_tg_check(par, par->targinfo);
280}
281
282static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
283{
284 struct xt_ct_target_info_v1 *info = par->targinfo;
285
286 if (info->flags & ~XT_CT_MASK)
287 return -EINVAL;
288
d52ed437 289 return xt_ct_tg_check(par, par->targinfo);
84f3bb9a
PM
290}
291
236df005 292static void xt_ct_destroy_timeout(struct nf_conn *ct)
24de58f4 293{
24de58f4
PNA
294#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
295 struct nf_conn_timeout *timeout_ext;
296 typeof(nf_ct_timeout_put_hook) timeout_put;
236df005
PNA
297
298 rcu_read_lock();
299 timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
300
301 if (timeout_put) {
302 timeout_ext = nf_ct_timeout_find(ct);
303 if (timeout_ext)
304 timeout_put(timeout_ext->timeout);
305 }
306 rcu_read_unlock();
24de58f4 307#endif
236df005
PNA
308}
309
d52ed437
PNA
310static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
311 struct xt_ct_target_info_v1 *info)
236df005 312{
236df005
PNA
313 struct nf_conn *ct = info->ct;
314 struct nf_conn_help *help;
315
27e7190e 316 if (ct && !nf_ct_is_untracked(ct)) {
24de58f4
PNA
317 help = nfct_help(ct);
318 if (help)
319 module_put(help->helper->me);
320
321 nf_ct_l3proto_module_put(par->family);
322
236df005 323 xt_ct_destroy_timeout(ct);
27e7190e 324 nf_ct_put(info->ct);
24de58f4 325 }
d52ed437
PNA
326}
327
328static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
329{
330 struct xt_ct_target_info *info = par->targinfo;
331 struct xt_ct_target_info_v1 info_v1 = {
332 .flags = info->flags,
333 .zone = info->zone,
334 .ct_events = info->ct_events,
335 .exp_events = info->exp_events,
336 .ct = info->ct,
337 };
338 memcpy(info_v1.helper, info->helper, sizeof(info->helper));
339
340 xt_ct_tg_destroy(par, &info_v1);
341}
342
343static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
344{
345 xt_ct_tg_destroy(par, par->targinfo);
24de58f4
PNA
346}
347
348static struct xt_target xt_ct_tg_reg[] __read_mostly = {
349 {
350 .name = "CT",
351 .family = NFPROTO_UNSPEC,
352 .targetsize = sizeof(struct xt_ct_target_info),
353 .checkentry = xt_ct_tg_check_v0,
354 .destroy = xt_ct_tg_destroy_v0,
355 .target = xt_ct_target_v0,
356 .table = "raw",
357 .me = THIS_MODULE,
358 },
359 {
360 .name = "CT",
361 .family = NFPROTO_UNSPEC,
362 .revision = 1,
363 .targetsize = sizeof(struct xt_ct_target_info_v1),
364 .checkentry = xt_ct_tg_check_v1,
365 .destroy = xt_ct_tg_destroy_v1,
366 .target = xt_ct_target_v1,
367 .table = "raw",
368 .me = THIS_MODULE,
369 },
5474f57f
PNA
370 {
371 .name = "CT",
372 .family = NFPROTO_UNSPEC,
373 .revision = 2,
374 .targetsize = sizeof(struct xt_ct_target_info_v1),
375 .checkentry = xt_ct_tg_check_v2,
376 .destroy = xt_ct_tg_destroy_v1,
377 .target = xt_ct_target_v1,
378 .table = "raw",
379 .me = THIS_MODULE,
380 },
84f3bb9a
PM
381};
382
10db9069
PNA
383static unsigned int
384notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
385{
386 /* Previously seen (loopback)? Ignore. */
387 if (skb->nfct != NULL)
388 return XT_CONTINUE;
389
390 skb->nfct = &nf_ct_untracked_get()->ct_general;
391 skb->nfctinfo = IP_CT_NEW;
392 nf_conntrack_get(skb->nfct);
393
394 return XT_CONTINUE;
395}
396
397static int notrack_chk(const struct xt_tgchk_param *par)
398{
399 if (!par->net->xt.notrack_deprecated_warning) {
400 pr_info("netfilter: NOTRACK target is deprecated, "
401 "use CT instead or upgrade iptables\n");
402 par->net->xt.notrack_deprecated_warning = true;
403 }
404 return 0;
405}
406
407static struct xt_target notrack_tg_reg __read_mostly = {
408 .name = "NOTRACK",
409 .revision = 0,
410 .family = NFPROTO_UNSPEC,
411 .checkentry = notrack_chk,
412 .target = notrack_tg,
413 .table = "raw",
414 .me = THIS_MODULE,
415};
416
84f3bb9a
PM
417static int __init xt_ct_tg_init(void)
418{
10db9069
PNA
419 int ret;
420
421 ret = xt_register_target(&notrack_tg_reg);
422 if (ret < 0)
423 return ret;
424
425 ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
426 if (ret < 0) {
427 xt_unregister_target(&notrack_tg_reg);
428 return ret;
429 }
430 return 0;
84f3bb9a
PM
431}
432
433static void __exit xt_ct_tg_exit(void)
434{
24de58f4 435 xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
10db9069 436 xt_unregister_target(&notrack_tg_reg);
84f3bb9a
PM
437}
438
439module_init(xt_ct_tg_init);
440module_exit(xt_ct_tg_exit);
441
442MODULE_LICENSE("GPL");
443MODULE_DESCRIPTION("Xtables: connection tracking target");
444MODULE_ALIAS("ipt_CT");
445MODULE_ALIAS("ip6t_CT");
10db9069
PNA
446MODULE_ALIAS("ipt_NOTRACK");
447MODULE_ALIAS("ip6t_NOTRACK");
This page took 0.236452 seconds and 5 git commands to generate.