Commit | Line | Data |
---|---|---|
1da177e4 LT |
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> | |
1da177e4 LT |
17 | #include <linux/types.h> |
18 | #include <linux/kernel.h> | |
1da177e4 LT |
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 | ||
1da177e4 | 40 | |
e9ce1cd3 DM |
41 | #define IPT_TAB_MASK 15 |
42 | static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1]; | |
43 | static u32 ipt_idx_gen; | |
1da177e4 LT |
44 | static DEFINE_RWLOCK(ipt_lock); |
45 | ||
e9ce1cd3 DM |
46 | static struct tcf_hashinfo ipt_hash_info = { |
47 | .htab = tcf_ipt_ht, | |
48 | .hmask = IPT_TAB_MASK, | |
49 | .lock = &ipt_lock, | |
50 | }; | |
1da177e4 | 51 | |
e9ce1cd3 | 52 | static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook) |
1da177e4 | 53 | { |
e60a13e0 | 54 | struct xt_target *target; |
1da177e4 LT |
55 | int ret = 0; |
56 | ||
239a87c8 PM |
57 | target = xt_request_find_target(AF_INET, t->u.user.name, |
58 | t->u.user.revision); | |
1da177e4 LT |
59 | if (!target) |
60 | return -ENOENT; | |
61 | ||
1da177e4 LT |
62 | t->u.kernel.target = target; |
63 | ||
18118cdb PM |
64 | ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), |
65 | table, hook, 0, 0); | |
239a87c8 PM |
66 | if (ret) { |
67 | module_put(t->u.kernel.target->me); | |
18118cdb | 68 | return ret; |
239a87c8 | 69 | } |
1da177e4 | 70 | if (t->u.kernel.target->checkentry |
1c524830 | 71 | && !t->u.kernel.target->checkentry(table, NULL, |
10297b99 | 72 | t->u.kernel.target, t->data, |
1da177e4 | 73 | hook)) { |
1da177e4 LT |
74 | module_put(t->u.kernel.target->me); |
75 | ret = -EINVAL; | |
76 | } | |
77 | ||
78 | return ret; | |
79 | } | |
80 | ||
e9ce1cd3 | 81 | static void ipt_destroy_target(struct ipt_entry_target *t) |
1da177e4 LT |
82 | { |
83 | if (t->u.kernel.target->destroy) | |
efa74165 | 84 | t->u.kernel.target->destroy(t->u.kernel.target, t->data); |
10297b99 | 85 | module_put(t->u.kernel.target->me); |
1da177e4 LT |
86 | } |
87 | ||
e9ce1cd3 | 88 | static int tcf_ipt_release(struct tcf_ipt *ipt, int bind) |
1da177e4 LT |
89 | { |
90 | int ret = 0; | |
e9ce1cd3 | 91 | if (ipt) { |
1da177e4 | 92 | if (bind) |
e9ce1cd3 DM |
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); | |
1da177e4 LT |
100 | ret = ACT_P_DELETED; |
101 | } | |
102 | } | |
103 | return ret; | |
104 | } | |
105 | ||
e9ce1cd3 DM |
106 | static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est, |
107 | struct tc_action *a, int ovr, int bind) | |
1da177e4 LT |
108 | { |
109 | struct rtattr *tb[TCA_IPT_MAX]; | |
e9ce1cd3 DM |
110 | struct tcf_ipt *ipt; |
111 | struct tcf_common *pc; | |
1da177e4 LT |
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 | ||
e9ce1cd3 DM |
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)) | |
1da177e4 LT |
140 | return -ENOMEM; |
141 | ret = ACT_P_CREATED; | |
142 | } else { | |
143 | if (!ovr) { | |
e9ce1cd3 | 144 | tcf_ipt_release(to_ipt(pc), bind); |
1da177e4 LT |
145 | return -EEXIST; |
146 | } | |
147 | } | |
e9ce1cd3 | 148 | ipt = to_ipt(pc); |
1da177e4 LT |
149 | |
150 | hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]); | |
151 | ||
152 | err = -ENOMEM; | |
153 | tname = kmalloc(IFNAMSIZ, GFP_KERNEL); | |
e9ce1cd3 | 154 | if (unlikely(!tname)) |
1da177e4 LT |
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 | ||
c7b1b249 | 160 | t = kmemdup(td, td->u.target_size, GFP_KERNEL); |
e9ce1cd3 | 161 | if (unlikely(!t)) |
1da177e4 | 162 | goto err2; |
1da177e4 LT |
163 | |
164 | if ((err = ipt_init_target(t, tname, hook)) < 0) | |
165 | goto err3; | |
166 | ||
e9ce1cd3 | 167 | spin_lock_bh(&ipt->tcf_lock); |
1da177e4 | 168 | if (ret != ACT_P_CREATED) { |
e9ce1cd3 DM |
169 | ipt_destroy_target(ipt->tcfi_t); |
170 | kfree(ipt->tcfi_tname); | |
171 | kfree(ipt->tcfi_t); | |
1da177e4 | 172 | } |
e9ce1cd3 DM |
173 | ipt->tcfi_tname = tname; |
174 | ipt->tcfi_t = t; | |
175 | ipt->tcfi_hook = hook; | |
176 | spin_unlock_bh(&ipt->tcf_lock); | |
1da177e4 | 177 | if (ret == ACT_P_CREATED) |
e9ce1cd3 | 178 | tcf_hash_insert(pc, &ipt_hash_info); |
1da177e4 LT |
179 | return ret; |
180 | ||
181 | err3: | |
182 | kfree(t); | |
183 | err2: | |
184 | kfree(tname); | |
185 | err1: | |
e9ce1cd3 | 186 | kfree(pc); |
1da177e4 LT |
187 | return err; |
188 | } | |
189 | ||
e9ce1cd3 | 190 | static int tcf_ipt_cleanup(struct tc_action *a, int bind) |
1da177e4 | 191 | { |
e9ce1cd3 DM |
192 | struct tcf_ipt *ipt = a->priv; |
193 | return tcf_ipt_release(ipt, bind); | |
1da177e4 LT |
194 | } |
195 | ||
e9ce1cd3 DM |
196 | static int tcf_ipt(struct sk_buff *skb, struct tc_action *a, |
197 | struct tcf_result *res) | |
1da177e4 LT |
198 | { |
199 | int ret = 0, result = 0; | |
e9ce1cd3 | 200 | struct tcf_ipt *ipt = a->priv; |
1da177e4 LT |
201 | |
202 | if (skb_cloned(skb)) { | |
203 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) | |
204 | return TC_ACT_UNSPEC; | |
205 | } | |
206 | ||
e9ce1cd3 | 207 | spin_lock(&ipt->tcf_lock); |
1da177e4 | 208 | |
e9ce1cd3 DM |
209 | ipt->tcf_tm.lastuse = jiffies; |
210 | ipt->tcf_bstats.bytes += skb->len; | |
211 | ipt->tcf_bstats.packets++; | |
1da177e4 LT |
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 | ||
f43c5a0d PM |
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 */ | |
e9ce1cd3 DM |
220 | ret = ipt->tcfi_t->u.kernel.target->target(&skb, skb->dev, NULL, |
221 | ipt->tcfi_hook, | |
222 | ipt->tcfi_t->u.kernel.target, | |
fe1cb108 | 223 | ipt->tcfi_t->data); |
1da177e4 LT |
224 | switch (ret) { |
225 | case NF_ACCEPT: | |
226 | result = TC_ACT_OK; | |
227 | break; | |
228 | case NF_DROP: | |
229 | result = TC_ACT_SHOT; | |
e9ce1cd3 | 230 | ipt->tcf_qstats.drops++; |
1da177e4 LT |
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 | } | |
e9ce1cd3 | 241 | spin_unlock(&ipt->tcf_lock); |
1da177e4 LT |
242 | return result; |
243 | ||
244 | } | |
245 | ||
e9ce1cd3 | 246 | static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) |
1da177e4 | 247 | { |
e9ce1cd3 DM |
248 | unsigned char *b = skb->tail; |
249 | struct tcf_ipt *ipt = a->priv; | |
1da177e4 LT |
250 | struct ipt_entry_target *t; |
251 | struct tcf_t tm; | |
252 | struct tc_cnt c; | |
1da177e4 LT |
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 | ||
c7b1b249 | 259 | t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC); |
e9ce1cd3 | 260 | if (unlikely(!t)) |
1da177e4 LT |
261 | goto rtattr_failure; |
262 | ||
e9ce1cd3 DM |
263 | c.bindcnt = ipt->tcf_bindcnt - bind; |
264 | c.refcnt = ipt->tcf_refcnt - ref; | |
e9ce1cd3 DM |
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); | |
1da177e4 | 270 | RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c); |
e9ce1cd3 DM |
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); | |
1da177e4 LT |
275 | RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm); |
276 | kfree(t); | |
277 | return skb->len; | |
278 | ||
e9ce1cd3 | 279 | rtattr_failure: |
1da177e4 LT |
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", | |
e9ce1cd3 | 287 | .hinfo = &ipt_hash_info, |
1da177e4 LT |
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 | ||
e9ce1cd3 | 303 | static int __init ipt_init_module(void) |
1da177e4 LT |
304 | { |
305 | return tcf_register_action(&act_ipt_ops); | |
306 | } | |
307 | ||
e9ce1cd3 | 308 | static void __exit ipt_cleanup_module(void) |
1da177e4 LT |
309 | { |
310 | tcf_unregister_action(&act_ipt_ops); | |
311 | } | |
312 | ||
313 | module_init(ipt_init_module); | |
314 | module_exit(ipt_cleanup_module); |