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 struct tc_action_ops act_ipt_ops;
28 static struct tc_action_ops act_xt_ops;
30 static int ipt_init_target(struct net *net, struct xt_entry_target *t,
31 char *table, unsigned int hook)
33 struct xt_tgchk_param par;
34 struct xt_target *target;
35 struct ipt_entry e = {};
38 target = xt_request_find_target(AF_INET, t->u.user.name,
41 return PTR_ERR(target);
43 t->u.kernel.target = target;
44 memset(&par, 0, sizeof(par));
49 par.targinfo = t->data;
51 par.family = NFPROTO_IPV4;
53 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
55 module_put(t->u.kernel.target->me);
61 static void ipt_destroy_target(struct xt_entry_target *t, struct net *net)
63 struct xt_tgdtor_param par = {
64 .target = t->u.kernel.target,
66 .family = NFPROTO_IPV4,
69 if (par.target->destroy != NULL)
70 par.target->destroy(&par);
71 module_put(par.target->me);
74 static void tcf_ipt_release(struct tc_action *a)
76 struct tcf_ipt *ipt = to_ipt(a);
79 ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
82 kfree(ipt->tcfi_tname);
85 static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
86 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
87 [TCA_IPT_HOOK] = { .type = NLA_U32 },
88 [TCA_IPT_INDEX] = { .type = NLA_U32 },
89 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
92 static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
93 struct nlattr *est, struct tc_action **a,
94 const struct tc_action_ops *ops,
95 struct tcf_proto *tp, u32 flags)
97 struct tc_action_net *tn = net_generic(net, id);
98 bool bind = flags & TCA_ACT_FLAGS_BIND;
99 struct nlattr *tb[TCA_IPT_MAX + 1];
101 struct xt_entry_target *td, *t;
111 err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
116 if (tb[TCA_IPT_INDEX] != NULL)
117 index = nla_get_u32(tb[TCA_IPT_INDEX]);
119 err = tcf_idr_check_alloc(tn, &index, a, bind);
126 if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
128 tcf_idr_release(*a, bind);
130 tcf_idr_cleanup(tn, index);
134 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
135 if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
137 tcf_idr_release(*a, bind);
139 tcf_idr_cleanup(tn, index);
144 ret = tcf_idr_create(tn, index, est, a, ops, bind,
147 tcf_idr_cleanup(tn, index);
152 if (bind)/* dont override defaults */
155 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
156 tcf_idr_release(*a, bind);
160 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
163 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
164 if (unlikely(!tname))
166 if (tb[TCA_IPT_TABLE] == NULL ||
167 nla_strscpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
168 strcpy(tname, "mangle");
170 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
174 err = ipt_init_target(net, t, tname, hook);
180 spin_lock_bh(&ipt->tcf_lock);
181 if (ret != ACT_P_CREATED) {
182 ipt_destroy_target(ipt->tcfi_t, net);
183 kfree(ipt->tcfi_tname);
186 ipt->tcfi_tname = tname;
188 ipt->tcfi_hook = hook;
189 spin_unlock_bh(&ipt->tcf_lock);
197 tcf_idr_release(*a, bind);
201 static int tcf_ipt_init(struct net *net, struct nlattr *nla,
202 struct nlattr *est, struct tc_action **a,
203 struct tcf_proto *tp,
204 u32 flags, struct netlink_ext_ack *extack)
206 return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est,
207 a, &act_ipt_ops, tp, flags);
210 static int tcf_xt_init(struct net *net, struct nlattr *nla,
211 struct nlattr *est, struct tc_action **a,
212 struct tcf_proto *tp,
213 u32 flags, struct netlink_ext_ack *extack)
215 return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est,
216 a, &act_xt_ops, tp, flags);
219 static int tcf_ipt_act(struct sk_buff *skb, const struct tc_action *a,
220 struct tcf_result *res)
222 int ret = 0, result = 0;
223 struct tcf_ipt *ipt = to_ipt(a);
224 struct xt_action_param par;
225 struct nf_hook_state state = {
226 .net = dev_net(skb->dev),
228 .hook = ipt->tcfi_hook,
232 if (skb_unclone(skb, GFP_ATOMIC))
233 return TC_ACT_UNSPEC;
235 spin_lock(&ipt->tcf_lock);
237 tcf_lastuse_update(&ipt->tcf_tm);
238 bstats_update(&ipt->tcf_bstats, skb);
240 /* yes, we have to worry about both in and out dev
241 * worry later - danger - this API seems to have changed
242 * from earlier kernels
245 par.target = ipt->tcfi_t->u.kernel.target;
246 par.targinfo = ipt->tcfi_t->data;
247 ret = par.target->target(skb, &par);
254 result = TC_ACT_SHOT;
255 ipt->tcf_qstats.drops++;
258 result = TC_ACT_PIPE;
261 net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
266 spin_unlock(&ipt->tcf_lock);
271 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
274 unsigned char *b = skb_tail_pointer(skb);
275 struct tcf_ipt *ipt = to_ipt(a);
276 struct xt_entry_target *t;
280 /* for simple targets kernel size == user size
281 * user name = target name
282 * for foolproof you need to not assume this
285 spin_lock_bh(&ipt->tcf_lock);
286 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
288 goto nla_put_failure;
290 c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind;
291 c.refcnt = refcount_read(&ipt->tcf_refcnt) - ref;
292 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
294 if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) ||
295 nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) ||
296 nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) ||
297 nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) ||
298 nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
299 goto nla_put_failure;
301 tcf_tm_dump(&tm, &ipt->tcf_tm);
302 if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD))
303 goto nla_put_failure;
305 spin_unlock_bh(&ipt->tcf_lock);
310 spin_unlock_bh(&ipt->tcf_lock);
316 static struct tc_action_ops act_ipt_ops = {
319 .owner = THIS_MODULE,
321 .dump = tcf_ipt_dump,
322 .cleanup = tcf_ipt_release,
323 .init = tcf_ipt_init,
324 .size = sizeof(struct tcf_ipt),
327 static __net_init int ipt_init_net(struct net *net)
329 struct tc_action_net *tn = net_generic(net, act_ipt_ops.net_id);
331 return tc_action_net_init(net, tn, &act_ipt_ops);
334 static void __net_exit ipt_exit_net(struct list_head *net_list)
336 tc_action_net_exit(net_list, act_ipt_ops.net_id);
339 static struct pernet_operations ipt_net_ops = {
340 .init = ipt_init_net,
341 .exit_batch = ipt_exit_net,
342 .id = &act_ipt_ops.net_id,
343 .size = sizeof(struct tc_action_net),
346 static struct tc_action_ops act_xt_ops = {
349 .owner = THIS_MODULE,
351 .dump = tcf_ipt_dump,
352 .cleanup = tcf_ipt_release,
354 .size = sizeof(struct tcf_ipt),
357 static __net_init int xt_init_net(struct net *net)
359 struct tc_action_net *tn = net_generic(net, act_xt_ops.net_id);
361 return tc_action_net_init(net, tn, &act_xt_ops);
364 static void __net_exit xt_exit_net(struct list_head *net_list)
366 tc_action_net_exit(net_list, act_xt_ops.net_id);
369 static struct pernet_operations xt_net_ops = {
371 .exit_batch = xt_exit_net,
372 .id = &act_xt_ops.net_id,
373 .size = sizeof(struct tc_action_net),
376 MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
377 MODULE_DESCRIPTION("Iptables target actions");
378 MODULE_LICENSE("GPL");
379 MODULE_ALIAS("act_xt");
381 static int __init ipt_init_module(void)
385 ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
387 pr_err("Failed to load xt action\n");
389 ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
391 pr_err("Failed to load ipt action\n");
393 if (ret1 < 0 && ret2 < 0) {
399 static void __exit ipt_cleanup_module(void)
401 tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
402 tcf_unregister_action(&act_xt_ops, &xt_net_ops);
405 module_init(ipt_init_module);
406 module_exit(ipt_cleanup_module);