blob: 47f0b13242395d7b2e71447bdc1e9daaef2bba52 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * net/sched/ipt.c iptables target interface
3 *
4 *TODO: Add other tables. For now we only support the ipv4 table targets
5 *
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.
10 *
11 * Copyright: Jamal Hadi Salim (2002-4)
12 */
13
14#include <asm/uaccess.h>
15#include <asm/system.h>
16#include <asm/bitops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/types.h>
18#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/string.h>
20#include <linux/mm.h>
21#include <linux/socket.h>
22#include <linux/sockios.h>
23#include <linux/in.h>
24#include <linux/errno.h>
25#include <linux/interrupt.h>
26#include <linux/netdevice.h>
27#include <linux/skbuff.h>
28#include <linux/rtnetlink.h>
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/proc_fs.h>
32#include <linux/kmod.h>
33#include <net/sock.h>
34#include <net/pkt_sched.h>
35#include <linux/tc_act/tc_ipt.h>
36#include <net/tc_act/tc_ipt.h>
37
38#include <linux/netfilter_ipv4/ip_tables.h>
39
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
David S. Millere9ce1cd2006-08-21 23:54:55 -070041#define IPT_TAB_MASK 15
42static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
43static u32 ipt_idx_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044static DEFINE_RWLOCK(ipt_lock);
45
David S. Millere9ce1cd2006-08-21 23:54:55 -070046static struct tcf_hashinfo ipt_hash_info = {
47 .htab = tcf_ipt_ht,
48 .hmask = IPT_TAB_MASK,
49 .lock = &ipt_lock,
50};
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
David S. Millere9ce1cd2006-08-21 23:54:55 -070052static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
Linus Torvalds1da177e2005-04-16 15:20:36 -070053{
Jan Engelhardte60a13e2007-02-07 15:12:33 -080054 struct xt_target *target;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 int ret = 0;
56
Patrick McHardy239a87c2007-02-02 00:40:36 -080057 target = xt_request_find_target(AF_INET, t->u.user.name,
58 t->u.user.revision);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 if (!target)
60 return -ENOENT;
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 t->u.kernel.target = target;
63
Patrick McHardy18118cd2006-04-24 17:18:59 -070064 ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
65 table, hook, 0, 0);
Patrick McHardy239a87c2007-02-02 00:40:36 -080066 if (ret) {
67 module_put(t->u.kernel.target->me);
Patrick McHardy18118cd2006-04-24 17:18:59 -070068 return ret;
Patrick McHardy239a87c2007-02-02 00:40:36 -080069 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 if (t->u.kernel.target->checkentry
Patrick McHardy1c524832006-03-20 18:02:15 -080071 && !t->u.kernel.target->checkentry(table, NULL,
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090072 t->u.kernel.target, t->data,
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 hook)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 module_put(t->u.kernel.target->me);
75 ret = -EINVAL;
76 }
77
78 return ret;
79}
80
David S. Millere9ce1cd2006-08-21 23:54:55 -070081static void ipt_destroy_target(struct ipt_entry_target *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -070082{
83 if (t->u.kernel.target->destroy)
Patrick McHardyefa74162006-08-22 00:36:37 -070084 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090085 module_put(t->u.kernel.target->me);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086}
87
David S. Millere9ce1cd2006-08-21 23:54:55 -070088static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -070089{
90 int ret = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -070091 if (ipt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 if (bind)
David S. Millere9ce1cd2006-08-21 23:54:55 -070093 ipt->tcf_bindcnt--;
94 ipt->tcf_refcnt--;
95 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
96 ipt_destroy_target(ipt->tcfi_t);
97 kfree(ipt->tcfi_tname);
98 kfree(ipt->tcfi_t);
99 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 ret = ACT_P_DELETED;
101 }
102 }
103 return ret;
104}
105
David S. Millere9ce1cd2006-08-21 23:54:55 -0700106static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
107 struct tc_action *a, int ovr, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108{
109 struct rtattr *tb[TCA_IPT_MAX];
David S. Millere9ce1cd2006-08-21 23:54:55 -0700110 struct tcf_ipt *ipt;
111 struct tcf_common *pc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 struct ipt_entry_target *td, *t;
113 char *tname;
114 int ret = 0, err;
115 u32 hook = 0;
116 u32 index = 0;
117
118 if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
119 return -EINVAL;
120
121 if (tb[TCA_IPT_HOOK-1] == NULL ||
122 RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
123 return -EINVAL;
124 if (tb[TCA_IPT_TARG-1] == NULL ||
125 RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
126 return -EINVAL;
127 td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
128 if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
129 return -EINVAL;
130
131 if (tb[TCA_IPT_INDEX-1] != NULL &&
132 RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
133 index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]);
134
David S. Millere9ce1cd2006-08-21 23:54:55 -0700135 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
136 if (!pc) {
137 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
138 &ipt_idx_gen, &ipt_hash_info);
139 if (unlikely(!pc))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 return -ENOMEM;
141 ret = ACT_P_CREATED;
142 } else {
143 if (!ovr) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700144 tcf_ipt_release(to_ipt(pc), bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 return -EEXIST;
146 }
147 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700148 ipt = to_ipt(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
150 hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
151
152 err = -ENOMEM;
153 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700154 if (unlikely(!tname))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 goto err1;
156 if (tb[TCA_IPT_TABLE - 1] == NULL ||
157 rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
158 strcpy(tname, "mangle");
159
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200160 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700161 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 goto err2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
164 if ((err = ipt_init_target(t, tname, hook)) < 0)
165 goto err3;
166
David S. Millere9ce1cd2006-08-21 23:54:55 -0700167 spin_lock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 if (ret != ACT_P_CREATED) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700169 ipt_destroy_target(ipt->tcfi_t);
170 kfree(ipt->tcfi_tname);
171 kfree(ipt->tcfi_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700173 ipt->tcfi_tname = tname;
174 ipt->tcfi_t = t;
175 ipt->tcfi_hook = hook;
176 spin_unlock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 if (ret == ACT_P_CREATED)
David S. Millere9ce1cd2006-08-21 23:54:55 -0700178 tcf_hash_insert(pc, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 return ret;
180
181err3:
182 kfree(t);
183err2:
184 kfree(tname);
185err1:
David S. Millere9ce1cd2006-08-21 23:54:55 -0700186 kfree(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 return err;
188}
189
David S. Millere9ce1cd2006-08-21 23:54:55 -0700190static int tcf_ipt_cleanup(struct tc_action *a, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191{
David S. Millere9ce1cd2006-08-21 23:54:55 -0700192 struct tcf_ipt *ipt = a->priv;
193 return tcf_ipt_release(ipt, bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194}
195
David S. Millere9ce1cd2006-08-21 23:54:55 -0700196static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
197 struct tcf_result *res)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198{
199 int ret = 0, result = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700200 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 if (skb_cloned(skb)) {
203 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
204 return TC_ACT_UNSPEC;
205 }
206
David S. Millere9ce1cd2006-08-21 23:54:55 -0700207 spin_lock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
David S. Millere9ce1cd2006-08-21 23:54:55 -0700209 ipt->tcf_tm.lastuse = jiffies;
210 ipt->tcf_bstats.bytes += skb->len;
211 ipt->tcf_bstats.packets++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213 /* yes, we have to worry about both in and out dev
214 worry later - danger - this API seems to have changed
215 from earlier kernels */
216
Patrick McHardyf43c5a02006-01-08 22:15:34 -0800217 /* iptables targets take a double skb pointer in case the skb
218 * needs to be replaced. We don't own the skb, so this must not
219 * happen. The pskb_expand_head above should make sure of this */
David S. Millere9ce1cd2006-08-21 23:54:55 -0700220 ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL,
221 ipt->tcfi_hook,
222 ipt->tcfi_t->u.kernel.target,
Patrick McHardyfe1cb102006-08-22 00:35:47 -0700223 ipt->tcfi_t->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 switch (ret) {
225 case NF_ACCEPT:
226 result = TC_ACT_OK;
227 break;
228 case NF_DROP:
229 result = TC_ACT_SHOT;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700230 ipt->tcf_qstats.drops++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 break;
232 case IPT_CONTINUE:
233 result = TC_ACT_PIPE;
234 break;
235 default:
236 if (net_ratelimit())
237 printk("Bogus netfilter code %d assume ACCEPT\n", ret);
238 result = TC_POLICE_OK;
239 break;
240 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700241 spin_unlock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 return result;
243
244}
245
David S. Millere9ce1cd2006-08-21 23:54:55 -0700246static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247{
David S. Millere9ce1cd2006-08-21 23:54:55 -0700248 unsigned char *b = skb->tail;
249 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 struct ipt_entry_target *t;
251 struct tcf_t tm;
252 struct tc_cnt c;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
254 /* for simple targets kernel size == user size
255 ** user name = target name
256 ** for foolproof you need to not assume this
257 */
258
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200259 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700260 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 goto rtattr_failure;
262
David S. Millere9ce1cd2006-08-21 23:54:55 -0700263 c.bindcnt = ipt->tcf_bindcnt - bind;
264 c.refcnt = ipt->tcf_refcnt - ref;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700265 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
David S. Millere9ce1cd2006-08-21 23:54:55 -0700267 RTA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
268 RTA_PUT(skb, TCA_IPT_INDEX, 4, &ipt->tcf_index);
269 RTA_PUT(skb, TCA_IPT_HOOK, 4, &ipt->tcfi_hook);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700271 RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, ipt->tcfi_tname);
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);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
276 kfree(t);
277 return skb->len;
278
David S. Millere9ce1cd2006-08-21 23:54:55 -0700279rtattr_failure:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 skb_trim(skb, b - skb->data);
281 kfree(t);
282 return -1;
283}
284
285static struct tc_action_ops act_ipt_ops = {
286 .kind = "ipt",
David S. Millere9ce1cd2006-08-21 23:54:55 -0700287 .hinfo = &ipt_hash_info,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 .type = TCA_ACT_IPT,
289 .capab = TCA_CAP_NONE,
290 .owner = THIS_MODULE,
291 .act = tcf_ipt,
292 .dump = tcf_ipt_dump,
293 .cleanup = tcf_ipt_cleanup,
294 .lookup = tcf_hash_search,
295 .init = tcf_ipt_init,
296 .walk = tcf_generic_walker
297};
298
299MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
300MODULE_DESCRIPTION("Iptables target actions");
301MODULE_LICENSE("GPL");
302
David S. Millere9ce1cd2006-08-21 23:54:55 -0700303static int __init ipt_init_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304{
305 return tcf_register_action(&act_ipt_ops);
306}
307
David S. Millere9ce1cd2006-08-21 23:54:55 -0700308static void __exit ipt_cleanup_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309{
310 tcf_unregister_action(&act_ipt_ops);
311}
312
313module_init(ipt_init_module);
314module_exit(ipt_cleanup_module);