blob: 00b05f422d45016195f124c81c1ab7d31aab62ab [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>
Arnaldo Carvalho de Melodc5fc572007-03-25 23:06:12 -070033#include <net/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <net/sock.h>
35#include <net/pkt_sched.h>
36#include <linux/tc_act/tc_ipt.h>
37#include <net/tc_act/tc_ipt.h>
38
39#include <linux/netfilter_ipv4/ip_tables.h>
40
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
David S. Millere9ce1cd2006-08-21 23:54:55 -070042#define IPT_TAB_MASK 15
43static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
44static u32 ipt_idx_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -070045static DEFINE_RWLOCK(ipt_lock);
46
David S. Millere9ce1cd2006-08-21 23:54:55 -070047static struct tcf_hashinfo ipt_hash_info = {
48 .htab = tcf_ipt_ht,
49 .hmask = IPT_TAB_MASK,
50 .lock = &ipt_lock,
51};
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
David S. Millere9ce1cd2006-08-21 23:54:55 -070053static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054{
Jan Engelhardte60a13e2007-02-07 15:12:33 -080055 struct xt_target *target;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 int ret = 0;
57
Patrick McHardy239a87c2007-02-02 00:40:36 -080058 target = xt_request_find_target(AF_INET, t->u.user.name,
59 t->u.user.revision);
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 if (!target)
61 return -ENOENT;
62
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 t->u.kernel.target = target;
64
Patrick McHardy18118cd2006-04-24 17:18:59 -070065 ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
66 table, hook, 0, 0);
Patrick McHardy239a87c2007-02-02 00:40:36 -080067 if (ret) {
68 module_put(t->u.kernel.target->me);
Patrick McHardy18118cd2006-04-24 17:18:59 -070069 return ret;
Patrick McHardy239a87c2007-02-02 00:40:36 -080070 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 if (t->u.kernel.target->checkentry
Patrick McHardy1c524832006-03-20 18:02:15 -080072 && !t->u.kernel.target->checkentry(table, NULL,
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090073 t->u.kernel.target, t->data,
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 hook)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 module_put(t->u.kernel.target->me);
76 ret = -EINVAL;
77 }
78
79 return ret;
80}
81
David S. Millere9ce1cd2006-08-21 23:54:55 -070082static void ipt_destroy_target(struct ipt_entry_target *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -070083{
84 if (t->u.kernel.target->destroy)
Patrick McHardyefa74162006-08-22 00:36:37 -070085 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090086 module_put(t->u.kernel.target->me);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087}
88
David S. Millere9ce1cd2006-08-21 23:54:55 -070089static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -070090{
91 int ret = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -070092 if (ipt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 if (bind)
David S. Millere9ce1cd2006-08-21 23:54:55 -070094 ipt->tcf_bindcnt--;
95 ipt->tcf_refcnt--;
96 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
97 ipt_destroy_target(ipt->tcfi_t);
98 kfree(ipt->tcfi_tname);
99 kfree(ipt->tcfi_t);
100 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 ret = ACT_P_DELETED;
102 }
103 }
104 return ret;
105}
106
David S. Millere9ce1cd2006-08-21 23:54:55 -0700107static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
108 struct tc_action *a, int ovr, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
110 struct rtattr *tb[TCA_IPT_MAX];
David S. Millere9ce1cd2006-08-21 23:54:55 -0700111 struct tcf_ipt *ipt;
112 struct tcf_common *pc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 struct ipt_entry_target *td, *t;
114 char *tname;
115 int ret = 0, err;
116 u32 hook = 0;
117 u32 index = 0;
118
119 if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
120 return -EINVAL;
121
122 if (tb[TCA_IPT_HOOK-1] == NULL ||
123 RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
124 return -EINVAL;
125 if (tb[TCA_IPT_TARG-1] == NULL ||
126 RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
127 return -EINVAL;
128 td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
129 if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
130 return -EINVAL;
131
132 if (tb[TCA_IPT_INDEX-1] != NULL &&
133 RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
134 index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]);
135
David S. Millere9ce1cd2006-08-21 23:54:55 -0700136 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
137 if (!pc) {
138 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
139 &ipt_idx_gen, &ipt_hash_info);
140 if (unlikely(!pc))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 return -ENOMEM;
142 ret = ACT_P_CREATED;
143 } else {
144 if (!ovr) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700145 tcf_ipt_release(to_ipt(pc), bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 return -EEXIST;
147 }
148 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700149 ipt = to_ipt(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
151 hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
152
153 err = -ENOMEM;
154 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700155 if (unlikely(!tname))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 goto err1;
157 if (tb[TCA_IPT_TABLE - 1] == NULL ||
158 rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
159 strcpy(tname, "mangle");
160
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200161 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700162 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 goto err2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
165 if ((err = ipt_init_target(t, tname, hook)) < 0)
166 goto err3;
167
David S. Millere9ce1cd2006-08-21 23:54:55 -0700168 spin_lock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 if (ret != ACT_P_CREATED) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700170 ipt_destroy_target(ipt->tcfi_t);
171 kfree(ipt->tcfi_tname);
172 kfree(ipt->tcfi_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700174 ipt->tcfi_tname = tname;
175 ipt->tcfi_t = t;
176 ipt->tcfi_hook = hook;
177 spin_unlock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 if (ret == ACT_P_CREATED)
David S. Millere9ce1cd2006-08-21 23:54:55 -0700179 tcf_hash_insert(pc, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 return ret;
181
182err3:
183 kfree(t);
184err2:
185 kfree(tname);
186err1:
David S. Millere9ce1cd2006-08-21 23:54:55 -0700187 kfree(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 return err;
189}
190
David S. Millere9ce1cd2006-08-21 23:54:55 -0700191static int tcf_ipt_cleanup(struct tc_action *a, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192{
David S. Millere9ce1cd2006-08-21 23:54:55 -0700193 struct tcf_ipt *ipt = a->priv;
194 return tcf_ipt_release(ipt, bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195}
196
David S. Millere9ce1cd2006-08-21 23:54:55 -0700197static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
198 struct tcf_result *res)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199{
200 int ret = 0, result = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700201 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202
203 if (skb_cloned(skb)) {
204 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
205 return TC_ACT_UNSPEC;
206 }
207
David S. Millere9ce1cd2006-08-21 23:54:55 -0700208 spin_lock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
David S. Millere9ce1cd2006-08-21 23:54:55 -0700210 ipt->tcf_tm.lastuse = jiffies;
211 ipt->tcf_bstats.bytes += skb->len;
212 ipt->tcf_bstats.packets++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
214 /* yes, we have to worry about both in and out dev
215 worry later - danger - this API seems to have changed
216 from earlier kernels */
217
Patrick McHardyf43c5a02006-01-08 22:15:34 -0800218 /* iptables targets take a double skb pointer in case the skb
219 * needs to be replaced. We don't own the skb, so this must not
220 * happen. The pskb_expand_head above should make sure of this */
David S. Millere9ce1cd2006-08-21 23:54:55 -0700221 ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL,
222 ipt->tcfi_hook,
223 ipt->tcfi_t->u.kernel.target,
Patrick McHardyfe1cb102006-08-22 00:35:47 -0700224 ipt->tcfi_t->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 switch (ret) {
226 case NF_ACCEPT:
227 result = TC_ACT_OK;
228 break;
229 case NF_DROP:
230 result = TC_ACT_SHOT;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700231 ipt->tcf_qstats.drops++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 break;
233 case IPT_CONTINUE:
234 result = TC_ACT_PIPE;
235 break;
236 default:
237 if (net_ratelimit())
238 printk("Bogus netfilter code %d assume ACCEPT\n", ret);
239 result = TC_POLICE_OK;
240 break;
241 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700242 spin_unlock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 return result;
244
245}
246
David S. Millere9ce1cd2006-08-21 23:54:55 -0700247static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700249 unsigned char *b = skb_tail_pointer(skb);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700250 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 struct ipt_entry_target *t;
252 struct tcf_t tm;
253 struct tc_cnt c;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254
255 /* for simple targets kernel size == user size
256 ** user name = target name
257 ** for foolproof you need to not assume this
258 */
259
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200260 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700261 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 goto rtattr_failure;
263
David S. Millere9ce1cd2006-08-21 23:54:55 -0700264 c.bindcnt = ipt->tcf_bindcnt - bind;
265 c.refcnt = ipt->tcf_refcnt - ref;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700266 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267
David S. Millere9ce1cd2006-08-21 23:54:55 -0700268 RTA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
269 RTA_PUT(skb, TCA_IPT_INDEX, 4, &ipt->tcf_index);
270 RTA_PUT(skb, TCA_IPT_HOOK, 4, &ipt->tcfi_hook);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700272 RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, ipt->tcfi_tname);
273 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
274 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
275 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
277 kfree(t);
278 return skb->len;
279
David S. Millere9ce1cd2006-08-21 23:54:55 -0700280rtattr_failure:
Arnaldo Carvalho de Melodc5fc572007-03-25 23:06:12 -0700281 nlmsg_trim(skb, b);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 kfree(t);
283 return -1;
284}
285
286static struct tc_action_ops act_ipt_ops = {
287 .kind = "ipt",
David S. Millere9ce1cd2006-08-21 23:54:55 -0700288 .hinfo = &ipt_hash_info,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 .type = TCA_ACT_IPT,
290 .capab = TCA_CAP_NONE,
291 .owner = THIS_MODULE,
292 .act = tcf_ipt,
293 .dump = tcf_ipt_dump,
294 .cleanup = tcf_ipt_cleanup,
295 .lookup = tcf_hash_search,
296 .init = tcf_ipt_init,
297 .walk = tcf_generic_walker
298};
299
300MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
301MODULE_DESCRIPTION("Iptables target actions");
302MODULE_LICENSE("GPL");
303
David S. Millere9ce1cd2006-08-21 23:54:55 -0700304static int __init ipt_init_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305{
306 return tcf_register_action(&act_ipt_ops);
307}
308
David S. Millere9ce1cd2006-08-21 23:54:55 -0700309static void __exit ipt_cleanup_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310{
311 tcf_unregister_action(&act_ipt_ops);
312}
313
314module_init(ipt_init_module);
315module_exit(ipt_cleanup_module);