2 * net/sched/ipt.c iptables target interface
4 *TODO: Add other tables. For now we only support the ipv4 table targets
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * Copyright: Jamal Hadi Salim (2002-13)
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/skbuff.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <net/netlink.h>
24 #include <net/pkt_sched.h>
25 #include <linux/tc_act/tc_ipt.h>
26 #include <net/tc_act/tc_ipt.h>
28 #include <linux/netfilter_ipv4/ip_tables.h>
31 #define IPT_TAB_MASK 15
32 static struct tcf_hashinfo ipt_hash_info;
34 static int ipt_init_target(struct xt_entry_target *t, char *table, unsigned int hook)
36 struct xt_tgchk_param par;
37 struct xt_target *target;
40 target = xt_request_find_target(AF_INET, t->u.user.name,
43 return PTR_ERR(target);
45 t->u.kernel.target = target;
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)
63 struct xt_tgdtor_param par = {
64 .target = t->u.kernel.target,
67 if (par.target->destroy != NULL)
68 par.target->destroy(&par);
69 module_put(par.target->me);
72 static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
79 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
80 ipt_destroy_target(ipt->tcfi_t);
81 kfree(ipt->tcfi_tname);
83 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
90 static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
91 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
92 [TCA_IPT_HOOK] = { .type = NLA_U32 },
93 [TCA_IPT_INDEX] = { .type = NLA_U32 },
94 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
97 static int tcf_ipt_init(struct net *net, struct nlattr *nla, struct nlattr *est,
98 struct tc_action *a, int ovr, int bind)
100 struct nlattr *tb[TCA_IPT_MAX + 1];
102 struct tcf_common *pc;
103 struct xt_entry_target *td, *t;
112 err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
116 if (tb[TCA_IPT_HOOK] == NULL)
118 if (tb[TCA_IPT_TARG] == NULL)
121 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
122 if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
125 if (tb[TCA_IPT_INDEX] != NULL)
126 index = nla_get_u32(tb[TCA_IPT_INDEX]);
128 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
130 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
136 if (bind)/* dont override defaults */
138 tcf_ipt_release(to_ipt(pc), bind);
145 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
148 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
149 if (unlikely(!tname))
151 if (tb[TCA_IPT_TABLE] == NULL ||
152 nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
153 strcpy(tname, "mangle");
155 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
159 err = ipt_init_target(t, tname, hook);
163 spin_lock_bh(&ipt->tcf_lock);
164 if (ret != ACT_P_CREATED) {
165 ipt_destroy_target(ipt->tcfi_t);
166 kfree(ipt->tcfi_tname);
169 ipt->tcfi_tname = tname;
171 ipt->tcfi_hook = hook;
172 spin_unlock_bh(&ipt->tcf_lock);
173 if (ret == ACT_P_CREATED)
174 tcf_hash_insert(pc, &ipt_hash_info);
182 if (ret == ACT_P_CREATED) {
184 gen_kill_estimator(&pc->tcfc_bstats,
186 kfree_rcu(pc, tcfc_rcu);
191 static int tcf_ipt_cleanup(struct tc_action *a, int bind)
193 struct tcf_ipt *ipt = a->priv;
194 return tcf_ipt_release(ipt, bind);
197 static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a,
198 struct tcf_result *res)
200 int ret = 0, result = 0;
201 struct tcf_ipt *ipt = a->priv;
202 struct xt_action_param par;
204 if (skb_unclone(skb, GFP_ATOMIC))
205 return TC_ACT_UNSPEC;
207 spin_lock(&ipt->tcf_lock);
209 ipt->tcf_tm.lastuse = jiffies;
210 bstats_update(&ipt->tcf_bstats, skb);
212 /* yes, we have to worry about both in and out dev
213 * worry later - danger - this API seems to have changed
214 * from earlier kernels
218 par.hooknum = ipt->tcfi_hook;
219 par.target = ipt->tcfi_t->u.kernel.target;
220 par.targinfo = ipt->tcfi_t->data;
221 ret = par.target->target(skb, &par);
228 result = TC_ACT_SHOT;
229 ipt->tcf_qstats.drops++;
232 result = TC_ACT_PIPE;
235 net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
237 result = TC_POLICE_OK;
240 spin_unlock(&ipt->tcf_lock);
245 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
247 unsigned char *b = skb_tail_pointer(skb);
248 struct tcf_ipt *ipt = a->priv;
249 struct xt_entry_target *t;
253 /* for simple targets kernel size == user size
254 * user name = target name
255 * for foolproof you need to not assume this
258 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
260 goto nla_put_failure;
262 c.bindcnt = ipt->tcf_bindcnt - bind;
263 c.refcnt = ipt->tcf_refcnt - ref;
264 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
266 if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) ||
267 nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) ||
268 nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) ||
269 nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) ||
270 nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
271 goto nla_put_failure;
272 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
273 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
274 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
275 if (nla_put(skb, TCA_IPT_TM, sizeof (tm), &tm))
276 goto nla_put_failure;
286 static struct tc_action_ops act_ipt_ops = {
288 .hinfo = &ipt_hash_info,
290 .capab = TCA_CAP_NONE,
291 .owner = THIS_MODULE,
293 .dump = tcf_ipt_dump,
294 .cleanup = tcf_ipt_cleanup,
295 .init = tcf_ipt_init,
298 static struct tc_action_ops act_xt_ops = {
300 .hinfo = &ipt_hash_info,
302 .capab = TCA_CAP_NONE,
303 .owner = THIS_MODULE,
305 .dump = tcf_ipt_dump,
306 .cleanup = tcf_ipt_cleanup,
307 .init = tcf_ipt_init,
310 MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
311 MODULE_DESCRIPTION("Iptables target actions");
312 MODULE_LICENSE("GPL");
313 MODULE_ALIAS("act_xt");
315 static int __init ipt_init_module(void)
318 err = tcf_hashinfo_init(&ipt_hash_info, IPT_TAB_MASK);
322 ret1 = tcf_register_action(&act_xt_ops);
324 printk("Failed to load xt action\n");
325 ret2 = tcf_register_action(&act_ipt_ops);
327 printk("Failed to load ipt action\n");
329 if (ret1 < 0 && ret2 < 0) {
330 tcf_hashinfo_destroy(&ipt_hash_info);
336 static void __exit ipt_cleanup_module(void)
338 tcf_unregister_action(&act_xt_ops);
339 tcf_unregister_action(&act_ipt_ops);
340 tcf_hashinfo_destroy(&ipt_hash_info);
343 module_init(ipt_init_module);
344 module_exit(ipt_cleanup_module);