blob: a9608064a4c303cb884b0fc6913d1f68e2fd33ee [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>
19#include <linux/sched.h>
20#include <linux/string.h>
21#include <linux/mm.h>
22#include <linux/socket.h>
23#include <linux/sockios.h>
24#include <linux/in.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>
34#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{
55 struct ipt_target *target;
56 int ret = 0;
57
Harald Welte2e4e6a12006-01-12 13:30:04 -080058 target = xt_find_target(AF_INET, t->u.user.name, 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);
66 if (ret)
67 return ret;
68
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 if (t->u.kernel.target->checkentry
Patrick McHardy1c524832006-03-20 18:02:15 -080070 && !t->u.kernel.target->checkentry(table, NULL,
71 t->u.kernel.target, t->data,
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 hook)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 module_put(t->u.kernel.target->me);
74 ret = -EINVAL;
75 }
76
77 return ret;
78}
79
David S. Millere9ce1cd2006-08-21 23:54:55 -070080static void ipt_destroy_target(struct ipt_entry_target *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -070081{
82 if (t->u.kernel.target->destroy)
Patrick McHardyefa74162006-08-22 00:36:37 -070083 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 module_put(t->u.kernel.target->me);
85}
86
David S. Millere9ce1cd2006-08-21 23:54:55 -070087static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
89 int ret = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -070090 if (ipt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 if (bind)
David S. Millere9ce1cd2006-08-21 23:54:55 -070092 ipt->tcf_bindcnt--;
93 ipt->tcf_refcnt--;
94 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
95 ipt_destroy_target(ipt->tcfi_t);
96 kfree(ipt->tcfi_tname);
97 kfree(ipt->tcfi_t);
98 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 ret = ACT_P_DELETED;
100 }
101 }
102 return ret;
103}
104
David S. Millere9ce1cd2006-08-21 23:54:55 -0700105static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
106 struct tc_action *a, int ovr, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107{
108 struct rtattr *tb[TCA_IPT_MAX];
David S. Millere9ce1cd2006-08-21 23:54:55 -0700109 struct tcf_ipt *ipt;
110 struct tcf_common *pc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 struct ipt_entry_target *td, *t;
112 char *tname;
113 int ret = 0, err;
114 u32 hook = 0;
115 u32 index = 0;
116
117 if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
118 return -EINVAL;
119
120 if (tb[TCA_IPT_HOOK-1] == NULL ||
121 RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
122 return -EINVAL;
123 if (tb[TCA_IPT_TARG-1] == NULL ||
124 RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
125 return -EINVAL;
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)
128 return -EINVAL;
129
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]);
133
David S. Millere9ce1cd2006-08-21 23:54:55 -0700134 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
135 if (!pc) {
136 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
137 &ipt_idx_gen, &ipt_hash_info);
138 if (unlikely(!pc))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 return -ENOMEM;
140 ret = ACT_P_CREATED;
141 } else {
142 if (!ovr) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700143 tcf_ipt_release(to_ipt(pc), bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 return -EEXIST;
145 }
146 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700147 ipt = to_ipt(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148
149 hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
150
151 err = -ENOMEM;
152 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700153 if (unlikely(!tname))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 goto err1;
155 if (tb[TCA_IPT_TABLE - 1] == NULL ||
156 rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
157 strcpy(tname, "mangle");
158
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200159 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700160 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 goto err2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
163 if ((err = ipt_init_target(t, tname, hook)) < 0)
164 goto err3;
165
David S. Millere9ce1cd2006-08-21 23:54:55 -0700166 spin_lock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 if (ret != ACT_P_CREATED) {
David S. Millere9ce1cd2006-08-21 23:54:55 -0700168 ipt_destroy_target(ipt->tcfi_t);
169 kfree(ipt->tcfi_tname);
170 kfree(ipt->tcfi_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700172 ipt->tcfi_tname = tname;
173 ipt->tcfi_t = t;
174 ipt->tcfi_hook = hook;
175 spin_unlock_bh(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 if (ret == ACT_P_CREATED)
David S. Millere9ce1cd2006-08-21 23:54:55 -0700177 tcf_hash_insert(pc, &ipt_hash_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 return ret;
179
180err3:
181 kfree(t);
182err2:
183 kfree(tname);
184err1:
David S. Millere9ce1cd2006-08-21 23:54:55 -0700185 kfree(pc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 return err;
187}
188
David S. Millere9ce1cd2006-08-21 23:54:55 -0700189static int tcf_ipt_cleanup(struct tc_action *a, int bind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190{
David S. Millere9ce1cd2006-08-21 23:54:55 -0700191 struct tcf_ipt *ipt = a->priv;
192 return tcf_ipt_release(ipt, bind);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193}
194
David S. Millere9ce1cd2006-08-21 23:54:55 -0700195static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
196 struct tcf_result *res)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197{
198 int ret = 0, result = 0;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700199 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
201 if (skb_cloned(skb)) {
202 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
203 return TC_ACT_UNSPEC;
204 }
205
David S. Millere9ce1cd2006-08-21 23:54:55 -0700206 spin_lock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
David S. Millere9ce1cd2006-08-21 23:54:55 -0700208 ipt->tcf_tm.lastuse = jiffies;
209 ipt->tcf_bstats.bytes += skb->len;
210 ipt->tcf_bstats.packets++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211
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 */
215
Patrick McHardyf43c5a02006-01-08 22:15:34 -0800216 /* 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 */
David S. Millere9ce1cd2006-08-21 23:54:55 -0700219 ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL,
220 ipt->tcfi_hook,
221 ipt->tcfi_t->u.kernel.target,
Patrick McHardyfe1cb102006-08-22 00:35:47 -0700222 ipt->tcfi_t->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 switch (ret) {
224 case NF_ACCEPT:
225 result = TC_ACT_OK;
226 break;
227 case NF_DROP:
228 result = TC_ACT_SHOT;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700229 ipt->tcf_qstats.drops++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 break;
231 case IPT_CONTINUE:
232 result = TC_ACT_PIPE;
233 break;
234 default:
235 if (net_ratelimit())
236 printk("Bogus netfilter code %d assume ACCEPT\n", ret);
237 result = TC_POLICE_OK;
238 break;
239 }
David S. Millere9ce1cd2006-08-21 23:54:55 -0700240 spin_unlock(&ipt->tcf_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 return result;
242
243}
244
David S. Millere9ce1cd2006-08-21 23:54:55 -0700245static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246{
David S. Millere9ce1cd2006-08-21 23:54:55 -0700247 unsigned char *b = skb->tail;
248 struct tcf_ipt *ipt = a->priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 struct ipt_entry_target *t;
250 struct tcf_t tm;
251 struct tc_cnt c;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252
253 /* for simple targets kernel size == user size
254 ** user name = target name
255 ** for foolproof you need to not assume this
256 */
257
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200258 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700259 if (unlikely(!t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 goto rtattr_failure;
261
David S. Millere9ce1cd2006-08-21 23:54:55 -0700262 c.bindcnt = ipt->tcf_bindcnt - bind;
263 c.refcnt = ipt->tcf_refcnt - ref;
David S. Millere9ce1cd2006-08-21 23:54:55 -0700264 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265
David S. Millere9ce1cd2006-08-21 23:54:55 -0700266 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);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
David S. Millere9ce1cd2006-08-21 23:54:55 -0700270 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);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
275 kfree(t);
276 return skb->len;
277
David S. Millere9ce1cd2006-08-21 23:54:55 -0700278rtattr_failure:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 skb_trim(skb, b - skb->data);
280 kfree(t);
281 return -1;
282}
283
284static struct tc_action_ops act_ipt_ops = {
285 .kind = "ipt",
David S. Millere9ce1cd2006-08-21 23:54:55 -0700286 .hinfo = &ipt_hash_info,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 .type = TCA_ACT_IPT,
288 .capab = TCA_CAP_NONE,
289 .owner = THIS_MODULE,
290 .act = tcf_ipt,
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
296};
297
298MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
299MODULE_DESCRIPTION("Iptables target actions");
300MODULE_LICENSE("GPL");
301
David S. Millere9ce1cd2006-08-21 23:54:55 -0700302static int __init ipt_init_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303{
304 return tcf_register_action(&act_ipt_ops);
305}
306
David S. Millere9ce1cd2006-08-21 23:54:55 -0700307static void __exit ipt_cleanup_module(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308{
309 tcf_unregister_action(&act_ipt_ops);
310}
311
312module_init(ipt_init_module);
313module_exit(ipt_cleanup_module);