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>
23 #include <net/tc_wrapper.h>
25 #include <linux/netfilter_ipv4/ip_tables.h>
28 static struct tc_action_ops act_ipt_ops;
29 static struct tc_action_ops act_xt_ops;
31 static int ipt_init_target(struct net *net, struct xt_entry_target *t,
32 char *table, unsigned int hook)
34 struct xt_tgchk_param par;
35 struct xt_target *target;
36 struct ipt_entry e = {};
39 target = xt_request_find_target(AF_INET, t->u.user.name,
42 return PTR_ERR(target);
44 t->u.kernel.target = target;
45 memset(&par, 0, sizeof(par));
50 par.targinfo = t->data;
52 par.family = NFPROTO_IPV4;
54 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
56 module_put(t->u.kernel.target->me);
62 static void ipt_destroy_target(struct xt_entry_target *t, struct net *net)
64 struct xt_tgdtor_param par = {
65 .target = t->u.kernel.target,
67 .family = NFPROTO_IPV4,
70 if (par.target->destroy != NULL)
71 par.target->destroy(&par);
72 module_put(par.target->me);
75 static void tcf_ipt_release(struct tc_action *a)
77 struct tcf_ipt *ipt = to_ipt(a);
80 ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
83 kfree(ipt->tcfi_tname);
86 static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
87 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
88 [TCA_IPT_HOOK] = { .type = NLA_U32 },
89 [TCA_IPT_INDEX] = { .type = NLA_U32 },
90 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
93 static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
94 struct nlattr *est, struct tc_action **a,
95 const struct tc_action_ops *ops,
96 struct tcf_proto *tp, u32 flags)
98 struct tc_action_net *tn = net_generic(net, id);
99 bool bind = flags & TCA_ACT_FLAGS_BIND;
100 struct nlattr *tb[TCA_IPT_MAX + 1];
102 struct xt_entry_target *td, *t;
112 err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
117 if (tb[TCA_IPT_INDEX] != NULL)
118 index = nla_get_u32(tb[TCA_IPT_INDEX]);
120 err = tcf_idr_check_alloc(tn, &index, a, bind);
127 if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
129 tcf_idr_release(*a, bind);
131 tcf_idr_cleanup(tn, index);
135 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
136 if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
138 tcf_idr_release(*a, bind);
140 tcf_idr_cleanup(tn, index);
145 ret = tcf_idr_create(tn, index, est, a, ops, bind,
148 tcf_idr_cleanup(tn, index);
153 if (bind)/* dont override defaults */
156 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
157 tcf_idr_release(*a, bind);
161 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
164 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
165 if (unlikely(!tname))
167 if (tb[TCA_IPT_TABLE] == NULL ||
168 nla_strscpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
169 strcpy(tname, "mangle");
171 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
175 err = ipt_init_target(net, t, tname, hook);
181 spin_lock_bh(&ipt->tcf_lock);
182 if (ret != ACT_P_CREATED) {
183 ipt_destroy_target(ipt->tcfi_t, net);
184 kfree(ipt->tcfi_tname);
187 ipt->tcfi_tname = tname;
189 ipt->tcfi_hook = hook;
190 spin_unlock_bh(&ipt->tcf_lock);
198 tcf_idr_release(*a, bind);
202 static int tcf_ipt_init(struct net *net, struct nlattr *nla,
203 struct nlattr *est, struct tc_action **a,
204 struct tcf_proto *tp,
205 u32 flags, struct netlink_ext_ack *extack)
207 return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est,
208 a, &act_ipt_ops, tp, flags);
211 static int tcf_xt_init(struct net *net, struct nlattr *nla,
212 struct nlattr *est, struct tc_action **a,
213 struct tcf_proto *tp,
214 u32 flags, struct netlink_ext_ack *extack)
216 return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est,
217 a, &act_xt_ops, tp, flags);
220 TC_INDIRECT_SCOPE int tcf_ipt_act(struct sk_buff *skb,
221 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 struct tc_action_ops act_ipt_ops = {
321 .owner = THIS_MODULE,
323 .dump = tcf_ipt_dump,
324 .cleanup = tcf_ipt_release,
325 .init = tcf_ipt_init,
326 .size = sizeof(struct tcf_ipt),
329 static __net_init int ipt_init_net(struct net *net)
331 struct tc_action_net *tn = net_generic(net, act_ipt_ops.net_id);
333 return tc_action_net_init(net, tn, &act_ipt_ops);
336 static void __net_exit ipt_exit_net(struct list_head *net_list)
338 tc_action_net_exit(net_list, act_ipt_ops.net_id);
341 static struct pernet_operations ipt_net_ops = {
342 .init = ipt_init_net,
343 .exit_batch = ipt_exit_net,
344 .id = &act_ipt_ops.net_id,
345 .size = sizeof(struct tc_action_net),
348 static struct tc_action_ops act_xt_ops = {
351 .owner = THIS_MODULE,
353 .dump = tcf_ipt_dump,
354 .cleanup = tcf_ipt_release,
356 .size = sizeof(struct tcf_ipt),
359 static __net_init int xt_init_net(struct net *net)
361 struct tc_action_net *tn = net_generic(net, act_xt_ops.net_id);
363 return tc_action_net_init(net, tn, &act_xt_ops);
366 static void __net_exit xt_exit_net(struct list_head *net_list)
368 tc_action_net_exit(net_list, act_xt_ops.net_id);
371 static struct pernet_operations xt_net_ops = {
373 .exit_batch = xt_exit_net,
374 .id = &act_xt_ops.net_id,
375 .size = sizeof(struct tc_action_net),
378 MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
379 MODULE_DESCRIPTION("Iptables target actions");
380 MODULE_LICENSE("GPL");
381 MODULE_ALIAS("act_xt");
383 static int __init ipt_init_module(void)
387 ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
389 pr_err("Failed to load xt action\n");
391 ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
393 pr_err("Failed to load ipt action\n");
395 if (ret1 < 0 && ret2 < 0) {
401 static void __exit ipt_cleanup_module(void)
403 tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
404 tcf_unregister_action(&act_xt_ops, &xt_net_ops);
407 module_init(ipt_init_module);
408 module_exit(ipt_cleanup_module);