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10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/errno.h>
14#include <linux/skbuff.h>
15#include <linux/rtnetlink.h>
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/slab.h>
19#include <net/netlink.h>
20#include <net/pkt_sched.h>
21#include <linux/tc_act/tc_ipt.h>
22#include <net/tc_act/tc_ipt.h>
23
24#include <linux/netfilter_ipv4/ip_tables.h>
25
26
27static unsigned int ipt_net_id;
28static struct tc_action_ops act_ipt_ops;
29
30static unsigned int xt_net_id;
31static struct tc_action_ops act_xt_ops;
32
33static int ipt_init_target(struct net *net, struct xt_entry_target *t,
34 char *table, unsigned int hook)
35{
36 struct xt_tgchk_param par;
37 struct xt_target *target;
38 struct ipt_entry e = {};
39 int ret = 0;
40
41 target = xt_request_find_target(AF_INET, t->u.user.name,
42 t->u.user.revision);
43 if (IS_ERR(target))
44 return PTR_ERR(target);
45
46 t->u.kernel.target = target;
47 memset(&par, 0, sizeof(par));
48 par.net = net;
49 par.table = table;
50 par.entryinfo = &e;
51 par.target = target;
52 par.targinfo = t->data;
53 par.hook_mask = hook;
54 par.family = NFPROTO_IPV4;
55
56 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
57 if (ret < 0) {
58 module_put(t->u.kernel.target->me);
59 return ret;
60 }
61 return 0;
62}
63
64static void ipt_destroy_target(struct xt_entry_target *t, struct net *net)
65{
66 struct xt_tgdtor_param par = {
67 .target = t->u.kernel.target,
68 .targinfo = t->data,
69 .family = NFPROTO_IPV4,
70 .net = net,
71 };
72 if (par.target->destroy != NULL)
73 par.target->destroy(&par);
74 module_put(par.target->me);
75}
76
77static void tcf_ipt_release(struct tc_action *a)
78{
79 struct tcf_ipt *ipt = to_ipt(a);
80
81 if (ipt->tcfi_t) {
82 ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
83 kfree(ipt->tcfi_t);
84 }
85 kfree(ipt->tcfi_tname);
86}
87
88static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
89 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
90 [TCA_IPT_HOOK] = { .type = NLA_U32 },
91 [TCA_IPT_INDEX] = { .type = NLA_U32 },
92 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
93};
94
95static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
96 struct nlattr *est, struct tc_action **a,
97 const struct tc_action_ops *ops, int ovr, int bind,
98 struct tcf_proto *tp, u32 flags)
99{
100 struct tc_action_net *tn = net_generic(net, id);
101 struct nlattr *tb[TCA_IPT_MAX + 1];
102 struct tcf_ipt *ipt;
103 struct xt_entry_target *td, *t;
104 char *tname;
105 bool exists = false;
106 int ret = 0, err;
107 u32 hook = 0;
108 u32 index = 0;
109
110 if (nla == NULL)
111 return -EINVAL;
112
113 err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
114 NULL);
115 if (err < 0)
116 return err;
117
118 if (tb[TCA_IPT_INDEX] != NULL)
119 index = nla_get_u32(tb[TCA_IPT_INDEX]);
120
121 err = tcf_idr_check_alloc(tn, &index, a, bind);
122 if (err < 0)
123 return err;
124 exists = err;
125 if (exists && bind)
126 return 0;
127
128 if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
129 if (exists)
130 tcf_idr_release(*a, bind);
131 else
132 tcf_idr_cleanup(tn, index);
133 return -EINVAL;
134 }
135
136 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
137 if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
138 if (exists)
139 tcf_idr_release(*a, bind);
140 else
141 tcf_idr_cleanup(tn, index);
142 return -EINVAL;
143 }
144
145 if (!exists) {
146 ret = tcf_idr_create(tn, index, est, a, ops, bind,
147 false, 0);
148 if (ret) {
149 tcf_idr_cleanup(tn, index);
150 return ret;
151 }
152 ret = ACT_P_CREATED;
153 } else {
154 if (bind)
155 return 0;
156
157 if (!ovr) {
158 tcf_idr_release(*a, bind);
159 return -EEXIST;
160 }
161 }
162 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
163
164 err = -ENOMEM;
165 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
166 if (unlikely(!tname))
167 goto err1;
168 if (tb[TCA_IPT_TABLE] == NULL ||
169 nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
170 strcpy(tname, "mangle");
171
172 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
173 if (unlikely(!t))
174 goto err2;
175
176 err = ipt_init_target(net, t, tname, hook);
177 if (err < 0)
178 goto err3;
179
180 ipt = to_ipt(*a);
181
182 spin_lock_bh(&ipt->tcf_lock);
183 if (ret != ACT_P_CREATED) {
184 ipt_destroy_target(ipt->tcfi_t, net);
185 kfree(ipt->tcfi_tname);
186 kfree(ipt->tcfi_t);
187 }
188 ipt->tcfi_tname = tname;
189 ipt->tcfi_t = t;
190 ipt->tcfi_hook = hook;
191 spin_unlock_bh(&ipt->tcf_lock);
192 return ret;
193
194err3:
195 kfree(t);
196err2:
197 kfree(tname);
198err1:
199 tcf_idr_release(*a, bind);
200 return err;
201}
202
203static int tcf_ipt_init(struct net *net, struct nlattr *nla,
204 struct nlattr *est, struct tc_action **a, int ovr,
205 int bind, bool rtnl_held, struct tcf_proto *tp,
206 u32 flags, struct netlink_ext_ack *extack)
207{
208 return __tcf_ipt_init(net, ipt_net_id, nla, est, a, &act_ipt_ops, ovr,
209 bind, tp, flags);
210}
211
212static int tcf_xt_init(struct net *net, struct nlattr *nla,
213 struct nlattr *est, struct tc_action **a, int ovr,
214 int bind, bool unlocked, struct tcf_proto *tp,
215 u32 flags, struct netlink_ext_ack *extack)
216{
217 return __tcf_ipt_init(net, xt_net_id, nla, est, a, &act_xt_ops, ovr,
218 bind, tp, flags);
219}
220
221static int tcf_ipt_act(struct sk_buff *skb, const struct tc_action *a,
222 struct tcf_result *res)
223{
224 int ret = 0, result = 0;
225 struct tcf_ipt *ipt = to_ipt(a);
226 struct xt_action_param par;
227 struct nf_hook_state state = {
228 .net = dev_net(skb->dev),
229 .in = skb->dev,
230 .hook = ipt->tcfi_hook,
231 .pf = NFPROTO_IPV4,
232 };
233
234 if (skb_unclone(skb, GFP_ATOMIC))
235 return TC_ACT_UNSPEC;
236
237 spin_lock(&ipt->tcf_lock);
238
239 tcf_lastuse_update(&ipt->tcf_tm);
240 bstats_update(&ipt->tcf_bstats, skb);
241
242
243
244
245
246 par.state = &state;
247 par.target = ipt->tcfi_t->u.kernel.target;
248 par.targinfo = ipt->tcfi_t->data;
249 ret = par.target->target(skb, &par);
250
251 switch (ret) {
252 case NF_ACCEPT:
253 result = TC_ACT_OK;
254 break;
255 case NF_DROP:
256 result = TC_ACT_SHOT;
257 ipt->tcf_qstats.drops++;
258 break;
259 case XT_CONTINUE:
260 result = TC_ACT_PIPE;
261 break;
262 default:
263 net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
264 ret);
265 result = TC_ACT_OK;
266 break;
267 }
268 spin_unlock(&ipt->tcf_lock);
269 return result;
270
271}
272
273static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
274 int ref)
275{
276 unsigned char *b = skb_tail_pointer(skb);
277 struct tcf_ipt *ipt = to_ipt(a);
278 struct xt_entry_target *t;
279 struct tcf_t tm;
280 struct tc_cnt c;
281
282
283
284
285
286
287 spin_lock_bh(&ipt->tcf_lock);
288 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
289 if (unlikely(!t))
290 goto nla_put_failure;
291
292 c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind;
293 c.refcnt = refcount_read(&ipt->tcf_refcnt) - ref;
294 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
295
296 if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) ||
297 nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) ||
298 nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) ||
299 nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) ||
300 nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
301 goto nla_put_failure;
302
303 tcf_tm_dump(&tm, &ipt->tcf_tm);
304 if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD))
305 goto nla_put_failure;
306
307 spin_unlock_bh(&ipt->tcf_lock);
308 kfree(t);
309 return skb->len;
310
311nla_put_failure:
312 spin_unlock_bh(&ipt->tcf_lock);
313 nlmsg_trim(skb, b);
314 kfree(t);
315 return -1;
316}
317
318static int tcf_ipt_walker(struct net *net, struct sk_buff *skb,
319 struct netlink_callback *cb, int type,
320 const struct tc_action_ops *ops,
321 struct netlink_ext_ack *extack)
322{
323 struct tc_action_net *tn = net_generic(net, ipt_net_id);
324
325 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
326}
327
328static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index)
329{
330 struct tc_action_net *tn = net_generic(net, ipt_net_id);
331
332 return tcf_idr_search(tn, a, index);
333}
334
335static struct tc_action_ops act_ipt_ops = {
336 .kind = "ipt",
337 .id = TCA_ID_IPT,
338 .owner = THIS_MODULE,
339 .act = tcf_ipt_act,
340 .dump = tcf_ipt_dump,
341 .cleanup = tcf_ipt_release,
342 .init = tcf_ipt_init,
343 .walk = tcf_ipt_walker,
344 .lookup = tcf_ipt_search,
345 .size = sizeof(struct tcf_ipt),
346};
347
348static __net_init int ipt_init_net(struct net *net)
349{
350 struct tc_action_net *tn = net_generic(net, ipt_net_id);
351
352 return tc_action_net_init(net, tn, &act_ipt_ops);
353}
354
355static void __net_exit ipt_exit_net(struct list_head *net_list)
356{
357 tc_action_net_exit(net_list, ipt_net_id);
358}
359
360static struct pernet_operations ipt_net_ops = {
361 .init = ipt_init_net,
362 .exit_batch = ipt_exit_net,
363 .id = &ipt_net_id,
364 .size = sizeof(struct tc_action_net),
365};
366
367static int tcf_xt_walker(struct net *net, struct sk_buff *skb,
368 struct netlink_callback *cb, int type,
369 const struct tc_action_ops *ops,
370 struct netlink_ext_ack *extack)
371{
372 struct tc_action_net *tn = net_generic(net, xt_net_id);
373
374 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
375}
376
377static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index)
378{
379 struct tc_action_net *tn = net_generic(net, xt_net_id);
380
381 return tcf_idr_search(tn, a, index);
382}
383
384static struct tc_action_ops act_xt_ops = {
385 .kind = "xt",
386 .id = TCA_ID_XT,
387 .owner = THIS_MODULE,
388 .act = tcf_ipt_act,
389 .dump = tcf_ipt_dump,
390 .cleanup = tcf_ipt_release,
391 .init = tcf_xt_init,
392 .walk = tcf_xt_walker,
393 .lookup = tcf_xt_search,
394 .size = sizeof(struct tcf_ipt),
395};
396
397static __net_init int xt_init_net(struct net *net)
398{
399 struct tc_action_net *tn = net_generic(net, xt_net_id);
400
401 return tc_action_net_init(net, tn, &act_xt_ops);
402}
403
404static void __net_exit xt_exit_net(struct list_head *net_list)
405{
406 tc_action_net_exit(net_list, xt_net_id);
407}
408
409static struct pernet_operations xt_net_ops = {
410 .init = xt_init_net,
411 .exit_batch = xt_exit_net,
412 .id = &xt_net_id,
413 .size = sizeof(struct tc_action_net),
414};
415
416MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
417MODULE_DESCRIPTION("Iptables target actions");
418MODULE_LICENSE("GPL");
419MODULE_ALIAS("act_xt");
420
421static int __init ipt_init_module(void)
422{
423 int ret1, ret2;
424
425 ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
426 if (ret1 < 0)
427 pr_err("Failed to load xt action\n");
428
429 ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
430 if (ret2 < 0)
431 pr_err("Failed to load ipt action\n");
432
433 if (ret1 < 0 && ret2 < 0) {
434 return ret1;
435 } else
436 return 0;
437}
438
439static void __exit ipt_cleanup_module(void)
440{
441 tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
442 tcf_unregister_action(&act_xt_ops, &xt_net_ops);
443}
444
445module_init(ipt_init_module);
446module_exit(ipt_cleanup_module);
447
