[PATCH] remove many unneeded #includes of sched.h
[linux-2.6.git] / net / sched / act_ipt.c
1 /*
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>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #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
40
41 #define IPT_TAB_MASK     15
42 static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
43 static u32 ipt_idx_gen;
44 static DEFINE_RWLOCK(ipt_lock);
45
46 static struct tcf_hashinfo ipt_hash_info = {
47         .htab   =       tcf_ipt_ht,
48         .hmask  =       IPT_TAB_MASK,
49         .lock   =       &ipt_lock,
50 };
51
52 static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
53 {
54         struct xt_target *target;
55         int ret = 0;
56
57         target = xt_request_find_target(AF_INET, t->u.user.name,
58                                         t->u.user.revision);
59         if (!target)
60                 return -ENOENT;
61
62         t->u.kernel.target = target;
63
64         ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
65                               table, hook, 0, 0);
66         if (ret) {
67                 module_put(t->u.kernel.target->me);
68                 return ret;
69         }
70         if (t->u.kernel.target->checkentry
71             && !t->u.kernel.target->checkentry(table, NULL,
72                                                t->u.kernel.target, t->data,
73                                                hook)) {
74                 module_put(t->u.kernel.target->me);
75                 ret = -EINVAL;
76         }
77
78         return ret;
79 }
80
81 static void ipt_destroy_target(struct ipt_entry_target *t)
82 {
83         if (t->u.kernel.target->destroy)
84                 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
85         module_put(t->u.kernel.target->me);
86 }
87
88 static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
89 {
90         int ret = 0;
91         if (ipt) {
92                 if (bind)
93                         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);
100                         ret = ACT_P_DELETED;
101                 }
102         }
103         return ret;
104 }
105
106 static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
107                         struct tc_action *a, int ovr, int bind)
108 {
109         struct rtattr *tb[TCA_IPT_MAX];
110         struct tcf_ipt *ipt;
111         struct tcf_common *pc;
112         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
135         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))
140                         return -ENOMEM;
141                 ret = ACT_P_CREATED;
142         } else {
143                 if (!ovr) {
144                         tcf_ipt_release(to_ipt(pc), bind);
145                         return -EEXIST;
146                 }
147         }
148         ipt = to_ipt(pc);
149
150         hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
151
152         err = -ENOMEM;
153         tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
154         if (unlikely(!tname))
155                 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
160         t = kmemdup(td, td->u.target_size, GFP_KERNEL);
161         if (unlikely(!t))
162                 goto err2;
163
164         if ((err = ipt_init_target(t, tname, hook)) < 0)
165                 goto err3;
166
167         spin_lock_bh(&ipt->tcf_lock);
168         if (ret != ACT_P_CREATED) {
169                 ipt_destroy_target(ipt->tcfi_t);
170                 kfree(ipt->tcfi_tname);
171                 kfree(ipt->tcfi_t);
172         }
173         ipt->tcfi_tname = tname;
174         ipt->tcfi_t     = t;
175         ipt->tcfi_hook  = hook;
176         spin_unlock_bh(&ipt->tcf_lock);
177         if (ret == ACT_P_CREATED)
178                 tcf_hash_insert(pc, &ipt_hash_info);
179         return ret;
180
181 err3:
182         kfree(t);
183 err2:
184         kfree(tname);
185 err1:
186         kfree(pc);
187         return err;
188 }
189
190 static int tcf_ipt_cleanup(struct tc_action *a, int bind)
191 {
192         struct tcf_ipt *ipt = a->priv;
193         return tcf_ipt_release(ipt, bind);
194 }
195
196 static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
197                    struct tcf_result *res)
198 {
199         int ret = 0, result = 0;
200         struct tcf_ipt *ipt = a->priv;
201
202         if (skb_cloned(skb)) {
203                 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
204                         return TC_ACT_UNSPEC;
205         }
206
207         spin_lock(&ipt->tcf_lock);
208
209         ipt->tcf_tm.lastuse = jiffies;
210         ipt->tcf_bstats.bytes += skb->len;
211         ipt->tcf_bstats.packets++;
212
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
217         /* 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 */
220         ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL,
221                                                    ipt->tcfi_hook,
222                                                    ipt->tcfi_t->u.kernel.target,
223                                                    ipt->tcfi_t->data);
224         switch (ret) {
225         case NF_ACCEPT:
226                 result = TC_ACT_OK;
227                 break;
228         case NF_DROP:
229                 result = TC_ACT_SHOT;
230                 ipt->tcf_qstats.drops++;
231                 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         }
241         spin_unlock(&ipt->tcf_lock);
242         return result;
243
244 }
245
246 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
247 {
248         unsigned char *b = skb->tail;
249         struct tcf_ipt *ipt = a->priv;
250         struct ipt_entry_target *t;
251         struct tcf_t tm;
252         struct tc_cnt c;
253
254         /* for simple targets kernel size == user size
255         ** user name = target name
256         ** for foolproof you need to not assume this
257         */
258
259         t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
260         if (unlikely(!t))
261                 goto rtattr_failure;
262
263         c.bindcnt = ipt->tcf_bindcnt - bind;
264         c.refcnt = ipt->tcf_refcnt - ref;
265         strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
266
267         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);
270         RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
271         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);
275         RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
276         kfree(t);
277         return skb->len;
278
279 rtattr_failure:
280         skb_trim(skb, b - skb->data);
281         kfree(t);
282         return -1;
283 }
284
285 static struct tc_action_ops act_ipt_ops = {
286         .kind           =       "ipt",
287         .hinfo          =       &ipt_hash_info,
288         .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
299 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
300 MODULE_DESCRIPTION("Iptables target actions");
301 MODULE_LICENSE("GPL");
302
303 static int __init ipt_init_module(void)
304 {
305         return tcf_register_action(&act_ipt_ops);
306 }
307
308 static void __exit ipt_cleanup_module(void)
309 {
310         tcf_unregister_action(&act_ipt_ops);
311 }
312
313 module_init(ipt_init_module);
314 module_exit(ipt_cleanup_module);