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 (2002-4)
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_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
33 static u32 ipt_idx_gen;
34 static DEFINE_RWLOCK(ipt_lock);
36 static struct tcf_hashinfo ipt_hash_info = {
38 .hmask = IPT_TAB_MASK,
42 static int ipt_init_target(struct xt_entry_target *t, char *table, unsigned int hook)
44 struct xt_tgchk_param par;
45 struct xt_target *target;
48 target = xt_request_find_target(AF_INET, t->u.user.name,
51 return PTR_ERR(target);
53 t->u.kernel.target = target;
57 par.targinfo = t->data;
59 par.family = NFPROTO_IPV4;
61 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
63 module_put(t->u.kernel.target->me);
69 static void ipt_destroy_target(struct xt_entry_target *t)
71 struct xt_tgdtor_param par = {
72 .target = t->u.kernel.target,
75 if (par.target->destroy != NULL)
76 par.target->destroy(&par);
77 module_put(par.target->me);
80 static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
87 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
88 ipt_destroy_target(ipt->tcfi_t);
89 kfree(ipt->tcfi_tname);
91 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
98 static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
99 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
100 [TCA_IPT_HOOK] = { .type = NLA_U32 },
101 [TCA_IPT_INDEX] = { .type = NLA_U32 },
102 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
105 static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est,
106 struct tc_action *a, int ovr, int bind)
108 struct nlattr *tb[TCA_IPT_MAX + 1];
110 struct tcf_common *pc;
111 struct xt_entry_target *td, *t;
120 err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
124 if (tb[TCA_IPT_HOOK] == NULL)
126 if (tb[TCA_IPT_TARG] == NULL)
129 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
130 if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
133 if (tb[TCA_IPT_INDEX] != NULL)
134 index = nla_get_u32(tb[TCA_IPT_INDEX]);
136 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
138 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
139 &ipt_idx_gen, &ipt_hash_info);
145 tcf_ipt_release(to_ipt(pc), bind);
151 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
154 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
155 if (unlikely(!tname))
157 if (tb[TCA_IPT_TABLE] == NULL ||
158 nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
159 strcpy(tname, "mangle");
161 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
165 err = ipt_init_target(t, tname, hook);
169 spin_lock_bh(&ipt->tcf_lock);
170 if (ret != ACT_P_CREATED) {
171 ipt_destroy_target(ipt->tcfi_t);
172 kfree(ipt->tcfi_tname);
175 ipt->tcfi_tname = tname;
177 ipt->tcfi_hook = hook;
178 spin_unlock_bh(&ipt->tcf_lock);
179 if (ret == ACT_P_CREATED)
180 tcf_hash_insert(pc, &ipt_hash_info);
188 if (ret == ACT_P_CREATED) {
190 gen_kill_estimator(&pc->tcfc_bstats,
192 kfree_rcu(pc, tcfc_rcu);
197 static int tcf_ipt_cleanup(struct tc_action *a, int bind)
199 struct tcf_ipt *ipt = a->priv;
200 return tcf_ipt_release(ipt, bind);
203 static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a,
204 struct tcf_result *res)
206 int ret = 0, result = 0;
207 struct tcf_ipt *ipt = a->priv;
208 struct xt_action_param par;
210 if (skb_cloned(skb)) {
211 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
212 return TC_ACT_UNSPEC;
215 spin_lock(&ipt->tcf_lock);
217 ipt->tcf_tm.lastuse = jiffies;
218 bstats_update(&ipt->tcf_bstats, skb);
220 /* yes, we have to worry about both in and out dev
221 * worry later - danger - this API seems to have changed
222 * from earlier kernels
226 par.hooknum = ipt->tcfi_hook;
227 par.target = ipt->tcfi_t->u.kernel.target;
228 par.targinfo = ipt->tcfi_t->data;
229 ret = par.target->target(skb, &par);
236 result = TC_ACT_SHOT;
237 ipt->tcf_qstats.drops++;
240 result = TC_ACT_PIPE;
243 net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
245 result = TC_POLICE_OK;
248 spin_unlock(&ipt->tcf_lock);
253 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
255 unsigned char *b = skb_tail_pointer(skb);
256 struct tcf_ipt *ipt = a->priv;
257 struct xt_entry_target *t;
261 /* for simple targets kernel size == user size
262 * user name = target name
263 * for foolproof you need to not assume this
266 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
268 goto nla_put_failure;
270 c.bindcnt = ipt->tcf_bindcnt - bind;
271 c.refcnt = ipt->tcf_refcnt - ref;
272 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
274 if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) ||
275 nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) ||
276 nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) ||
277 nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) ||
278 nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
279 goto nla_put_failure;
280 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
281 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
282 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
283 if (nla_put(skb, TCA_IPT_TM, sizeof (tm), &tm))
284 goto nla_put_failure;
294 static struct tc_action_ops act_ipt_ops = {
296 .hinfo = &ipt_hash_info,
298 .capab = TCA_CAP_NONE,
299 .owner = THIS_MODULE,
301 .dump = tcf_ipt_dump,
302 .cleanup = tcf_ipt_cleanup,
303 .lookup = tcf_hash_search,
304 .init = tcf_ipt_init,
305 .walk = tcf_generic_walker
308 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
309 MODULE_DESCRIPTION("Iptables target actions");
310 MODULE_LICENSE("GPL");
312 static int __init ipt_init_module(void)
314 return tcf_register_action(&act_ipt_ops);
317 static void __exit ipt_cleanup_module(void)
319 tcf_unregister_action(&act_ipt_ops);
322 module_init(ipt_init_module);
323 module_exit(ipt_cleanup_module);