1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * net/sched/act_ipt.c iptables target interface
5 *TODO: Add other tables. For now we only support the ipv4 table targets
7 * Copyright: Jamal Hadi Salim (2002-13)
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>
24 #include <linux/netfilter_ipv4/ip_tables.h>
27 static unsigned int ipt_net_id;
28 static struct tc_action_ops act_ipt_ops;
30 static unsigned int xt_net_id;
31 static struct tc_action_ops act_xt_ops;
33 static int ipt_init_target(struct net *net, struct xt_entry_target *t,
34 char *table, unsigned int hook)
36 struct xt_tgchk_param par;
37 struct xt_target *target;
38 struct ipt_entry e = {};
41 target = xt_request_find_target(AF_INET, t->u.user.name,
44 return PTR_ERR(target);
46 t->u.kernel.target = target;
47 memset(&par, 0, sizeof(par));
52 par.targinfo = t->data;
54 par.family = NFPROTO_IPV4;
56 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
58 module_put(t->u.kernel.target->me);
64 static void ipt_destroy_target(struct xt_entry_target *t, struct net *net)
66 struct xt_tgdtor_param par = {
67 .target = t->u.kernel.target,
69 .family = NFPROTO_IPV4,
72 if (par.target->destroy != NULL)
73 par.target->destroy(&par);
74 module_put(par.target->me);
77 static void tcf_ipt_release(struct tc_action *a)
79 struct tcf_ipt *ipt = to_ipt(a);
82 ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
85 kfree(ipt->tcfi_tname);
88 static 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) },
95 static 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)
100 struct tc_action_net *tn = net_generic(net, id);
101 struct nlattr *tb[TCA_IPT_MAX + 1];
103 struct xt_entry_target *td, *t;
113 err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
118 if (tb[TCA_IPT_INDEX] != NULL)
119 index = nla_get_u32(tb[TCA_IPT_INDEX]);
121 err = tcf_idr_check_alloc(tn, &index, a, bind);
128 if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
130 tcf_idr_release(*a, bind);
132 tcf_idr_cleanup(tn, index);
136 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
137 if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
139 tcf_idr_release(*a, bind);
141 tcf_idr_cleanup(tn, index);
146 ret = tcf_idr_create(tn, index, est, a, ops, bind,
149 tcf_idr_cleanup(tn, index);
154 if (bind)/* dont override defaults */
158 tcf_idr_release(*a, bind);
162 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
165 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
166 if (unlikely(!tname))
168 if (tb[TCA_IPT_TABLE] == NULL ||
169 nla_strscpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
170 strcpy(tname, "mangle");
172 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
176 err = ipt_init_target(net, t, tname, hook);
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);
188 ipt->tcfi_tname = tname;
190 ipt->tcfi_hook = hook;
191 spin_unlock_bh(&ipt->tcf_lock);
199 tcf_idr_release(*a, bind);
203 static 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)
208 return __tcf_ipt_init(net, ipt_net_id, nla, est, a, &act_ipt_ops, ovr,
212 static 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)
217 return __tcf_ipt_init(net, xt_net_id, nla, est, a, &act_xt_ops, ovr,
221 static int tcf_ipt_act(struct sk_buff *skb, const struct tc_action *a,
222 struct tcf_result *res)
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),
230 .hook = ipt->tcfi_hook,
234 if (skb_unclone(skb, GFP_ATOMIC))
235 return TC_ACT_UNSPEC;
237 spin_lock(&ipt->tcf_lock);
239 tcf_lastuse_update(&ipt->tcf_tm);
240 bstats_update(&ipt->tcf_bstats, skb);
242 /* yes, we have to worry about both in and out dev
243 * worry later - danger - this API seems to have changed
244 * from earlier kernels
247 par.target = ipt->tcfi_t->u.kernel.target;
248 par.targinfo = ipt->tcfi_t->data;
249 ret = par.target->target(skb, &par);
256 result = TC_ACT_SHOT;
257 ipt->tcf_qstats.drops++;
260 result = TC_ACT_PIPE;
263 net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
268 spin_unlock(&ipt->tcf_lock);
273 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
276 unsigned char *b = skb_tail_pointer(skb);
277 struct tcf_ipt *ipt = to_ipt(a);
278 struct xt_entry_target *t;
282 /* for simple targets kernel size == user size
283 * user name = target name
284 * for foolproof you need to not assume this
287 spin_lock_bh(&ipt->tcf_lock);
288 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
290 goto nla_put_failure;
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);
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;
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;
307 spin_unlock_bh(&ipt->tcf_lock);
312 spin_unlock_bh(&ipt->tcf_lock);
318 static 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)
323 struct tc_action_net *tn = net_generic(net, ipt_net_id);
325 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
328 static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index)
330 struct tc_action_net *tn = net_generic(net, ipt_net_id);
332 return tcf_idr_search(tn, a, index);
335 static struct tc_action_ops act_ipt_ops = {
338 .owner = THIS_MODULE,
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),
348 static __net_init int ipt_init_net(struct net *net)
350 struct tc_action_net *tn = net_generic(net, ipt_net_id);
352 return tc_action_net_init(net, tn, &act_ipt_ops);
355 static void __net_exit ipt_exit_net(struct list_head *net_list)
357 tc_action_net_exit(net_list, ipt_net_id);
360 static struct pernet_operations ipt_net_ops = {
361 .init = ipt_init_net,
362 .exit_batch = ipt_exit_net,
364 .size = sizeof(struct tc_action_net),
367 static 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)
372 struct tc_action_net *tn = net_generic(net, xt_net_id);
374 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
377 static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index)
379 struct tc_action_net *tn = net_generic(net, xt_net_id);
381 return tcf_idr_search(tn, a, index);
384 static struct tc_action_ops act_xt_ops = {
387 .owner = THIS_MODULE,
389 .dump = tcf_ipt_dump,
390 .cleanup = tcf_ipt_release,
392 .walk = tcf_xt_walker,
393 .lookup = tcf_xt_search,
394 .size = sizeof(struct tcf_ipt),
397 static __net_init int xt_init_net(struct net *net)
399 struct tc_action_net *tn = net_generic(net, xt_net_id);
401 return tc_action_net_init(net, tn, &act_xt_ops);
404 static void __net_exit xt_exit_net(struct list_head *net_list)
406 tc_action_net_exit(net_list, xt_net_id);
409 static struct pernet_operations xt_net_ops = {
411 .exit_batch = xt_exit_net,
413 .size = sizeof(struct tc_action_net),
416 MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
417 MODULE_DESCRIPTION("Iptables target actions");
418 MODULE_LICENSE("GPL");
419 MODULE_ALIAS("act_xt");
421 static int __init ipt_init_module(void)
425 ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
427 pr_err("Failed to load xt action\n");
429 ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
431 pr_err("Failed to load ipt action\n");
433 if (ret1 < 0 && ret2 < 0) {
439 static void __exit ipt_cleanup_module(void)
441 tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
442 tcf_unregister_action(&act_xt_ops, &xt_net_ops);
445 module_init(ipt_init_module);
446 module_exit(ipt_cleanup_module);