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 <asm/uaccess.h>
15 #include <asm/system.h>
16 #include <asm/bitops.h>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/string.h>
22 #include <linux/socket.h>
23 #include <linux/sockios.h>
25 #include <linux/errno.h>
26 #include <linux/interrupt.h>
27 #include <linux/netdevice.h>
28 #include <linux/skbuff.h>
29 #include <linux/rtnetlink.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/proc_fs.h>
33 #include <linux/kmod.h>
35 #include <net/pkt_sched.h>
36 #include <linux/tc_act/tc_ipt.h>
37 #include <net/tc_act/tc_ipt.h>
39 #include <linux/netfilter_ipv4/ip_tables.h>
42 #define IPT_TAB_MASK 15
43 static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
44 static u32 ipt_idx_gen;
45 static DEFINE_RWLOCK(ipt_lock);
47 static struct tcf_hashinfo ipt_hash_info = {
49 .hmask = IPT_TAB_MASK,
53 static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
55 struct ipt_target *target;
58 target = xt_find_target(AF_INET, t->u.user.name, t->u.user.revision);
62 t->u.kernel.target = target;
64 ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
69 if (t->u.kernel.target->checkentry
70 && !t->u.kernel.target->checkentry(table, NULL,
71 t->u.kernel.target, t->data,
73 module_put(t->u.kernel.target->me);
80 static void ipt_destroy_target(struct ipt_entry_target *t)
82 if (t->u.kernel.target->destroy)
83 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
84 module_put(t->u.kernel.target->me);
87 static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
94 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
95 ipt_destroy_target(ipt->tcfi_t);
96 kfree(ipt->tcfi_tname);
98 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
105 static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
106 struct tc_action *a, int ovr, int bind)
108 struct rtattr *tb[TCA_IPT_MAX];
110 struct tcf_common *pc;
111 struct ipt_entry_target *td, *t;
117 if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
120 if (tb[TCA_IPT_HOOK-1] == NULL ||
121 RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
123 if (tb[TCA_IPT_TARG-1] == NULL ||
124 RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
126 td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
127 if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
130 if (tb[TCA_IPT_INDEX-1] != NULL &&
131 RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
132 index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]);
134 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
136 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
137 &ipt_idx_gen, &ipt_hash_info);
143 tcf_ipt_release(to_ipt(pc), bind);
149 hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
152 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
153 if (unlikely(!tname))
155 if (tb[TCA_IPT_TABLE - 1] == NULL ||
156 rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
157 strcpy(tname, "mangle");
159 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
163 if ((err = ipt_init_target(t, tname, hook)) < 0)
166 spin_lock_bh(&ipt->tcf_lock);
167 if (ret != ACT_P_CREATED) {
168 ipt_destroy_target(ipt->tcfi_t);
169 kfree(ipt->tcfi_tname);
172 ipt->tcfi_tname = tname;
174 ipt->tcfi_hook = hook;
175 spin_unlock_bh(&ipt->tcf_lock);
176 if (ret == ACT_P_CREATED)
177 tcf_hash_insert(pc, &ipt_hash_info);
189 static int tcf_ipt_cleanup(struct tc_action *a, int bind)
191 struct tcf_ipt *ipt = a->priv;
192 return tcf_ipt_release(ipt, bind);
195 static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
196 struct tcf_result *res)
198 int ret = 0, result = 0;
199 struct tcf_ipt *ipt = a->priv;
201 if (skb_cloned(skb)) {
202 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
203 return TC_ACT_UNSPEC;
206 spin_lock(&ipt->tcf_lock);
208 ipt->tcf_tm.lastuse = jiffies;
209 ipt->tcf_bstats.bytes += skb->len;
210 ipt->tcf_bstats.packets++;
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 */
216 /* iptables targets take a double skb pointer in case the skb
217 * needs to be replaced. We don't own the skb, so this must not
218 * happen. The pskb_expand_head above should make sure of this */
219 ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL,
221 ipt->tcfi_t->u.kernel.target,
228 result = TC_ACT_SHOT;
229 ipt->tcf_qstats.drops++;
232 result = TC_ACT_PIPE;
236 printk("Bogus netfilter code %d assume ACCEPT\n", ret);
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;
248 struct tcf_ipt *ipt = a->priv;
249 struct ipt_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);
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 RTA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
267 RTA_PUT(skb, TCA_IPT_INDEX, 4, &ipt->tcf_index);
268 RTA_PUT(skb, TCA_IPT_HOOK, 4, &ipt->tcfi_hook);
269 RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
270 RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, ipt->tcfi_tname);
271 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
272 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
273 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
274 RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
279 skb_trim(skb, b - skb->data);
284 static struct tc_action_ops act_ipt_ops = {
286 .hinfo = &ipt_hash_info,
288 .capab = TCA_CAP_NONE,
289 .owner = THIS_MODULE,
291 .dump = tcf_ipt_dump,
292 .cleanup = tcf_ipt_cleanup,
293 .lookup = tcf_hash_search,
294 .init = tcf_ipt_init,
295 .walk = tcf_generic_walker
298 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
299 MODULE_DESCRIPTION("Iptables target actions");
300 MODULE_LICENSE("GPL");
302 static int __init ipt_init_module(void)
304 return tcf_register_action(&act_ipt_ops);
307 static void __exit ipt_cleanup_module(void)
309 tcf_unregister_action(&act_ipt_ops);
312 module_init(ipt_init_module);
313 module_exit(ipt_cleanup_module);