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 | ||
1da177e4 LT |
14 | #include <linux/types.h> |
15 | #include <linux/kernel.h> | |
1da177e4 | 16 | #include <linux/string.h> |
1da177e4 | 17 | #include <linux/errno.h> |
1da177e4 LT |
18 | #include <linux/skbuff.h> |
19 | #include <linux/rtnetlink.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/init.h> | |
dc5fc579 | 22 | #include <net/netlink.h> |
1da177e4 LT |
23 | #include <net/pkt_sched.h> |
24 | #include <linux/tc_act/tc_ipt.h> | |
25 | #include <net/tc_act/tc_ipt.h> | |
26 | ||
27 | #include <linux/netfilter_ipv4/ip_tables.h> | |
28 | ||
1da177e4 | 29 | |
e9ce1cd3 DM |
30 | #define IPT_TAB_MASK 15 |
31 | static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1]; | |
32 | static u32 ipt_idx_gen; | |
1da177e4 LT |
33 | static DEFINE_RWLOCK(ipt_lock); |
34 | ||
e9ce1cd3 DM |
35 | static struct tcf_hashinfo ipt_hash_info = { |
36 | .htab = tcf_ipt_ht, | |
37 | .hmask = IPT_TAB_MASK, | |
38 | .lock = &ipt_lock, | |
39 | }; | |
1da177e4 | 40 | |
e9ce1cd3 | 41 | static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook) |
1da177e4 | 42 | { |
e60a13e0 | 43 | struct xt_target *target; |
1da177e4 LT |
44 | int ret = 0; |
45 | ||
239a87c8 PM |
46 | target = xt_request_find_target(AF_INET, t->u.user.name, |
47 | t->u.user.revision); | |
1da177e4 LT |
48 | if (!target) |
49 | return -ENOENT; | |
50 | ||
1da177e4 LT |
51 | t->u.kernel.target = target; |
52 | ||
18118cdb PM |
53 | ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), |
54 | table, hook, 0, 0); | |
239a87c8 PM |
55 | if (ret) { |
56 | module_put(t->u.kernel.target->me); | |
18118cdb | 57 | return ret; |
239a87c8 | 58 | } |
1da177e4 | 59 | if (t->u.kernel.target->checkentry |
1c524830 | 60 | && !t->u.kernel.target->checkentry(table, NULL, |
10297b99 | 61 | t->u.kernel.target, t->data, |
1da177e4 | 62 | hook)) { |
1da177e4 LT |
63 | module_put(t->u.kernel.target->me); |
64 | ret = -EINVAL; | |
65 | } | |
66 | ||
67 | return ret; | |
68 | } | |
69 | ||
e9ce1cd3 | 70 | static void ipt_destroy_target(struct ipt_entry_target *t) |
1da177e4 LT |
71 | { |
72 | if (t->u.kernel.target->destroy) | |
efa74165 | 73 | t->u.kernel.target->destroy(t->u.kernel.target, t->data); |
10297b99 | 74 | module_put(t->u.kernel.target->me); |
1da177e4 LT |
75 | } |
76 | ||
e9ce1cd3 | 77 | static int tcf_ipt_release(struct tcf_ipt *ipt, int bind) |
1da177e4 LT |
78 | { |
79 | int ret = 0; | |
e9ce1cd3 | 80 | if (ipt) { |
1da177e4 | 81 | if (bind) |
e9ce1cd3 DM |
82 | ipt->tcf_bindcnt--; |
83 | ipt->tcf_refcnt--; | |
84 | if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) { | |
85 | ipt_destroy_target(ipt->tcfi_t); | |
86 | kfree(ipt->tcfi_tname); | |
87 | kfree(ipt->tcfi_t); | |
88 | tcf_hash_destroy(&ipt->common, &ipt_hash_info); | |
1da177e4 LT |
89 | ret = ACT_P_DELETED; |
90 | } | |
91 | } | |
92 | return ret; | |
93 | } | |
94 | ||
e9ce1cd3 DM |
95 | static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est, |
96 | struct tc_action *a, int ovr, int bind) | |
1da177e4 LT |
97 | { |
98 | struct rtattr *tb[TCA_IPT_MAX]; | |
e9ce1cd3 DM |
99 | struct tcf_ipt *ipt; |
100 | struct tcf_common *pc; | |
1da177e4 LT |
101 | struct ipt_entry_target *td, *t; |
102 | char *tname; | |
103 | int ret = 0, err; | |
104 | u32 hook = 0; | |
105 | u32 index = 0; | |
106 | ||
107 | if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0) | |
108 | return -EINVAL; | |
109 | ||
110 | if (tb[TCA_IPT_HOOK-1] == NULL || | |
111 | RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32)) | |
112 | return -EINVAL; | |
113 | if (tb[TCA_IPT_TARG-1] == NULL || | |
114 | RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t)) | |
115 | return -EINVAL; | |
116 | td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]); | |
117 | if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size) | |
118 | return -EINVAL; | |
119 | ||
120 | if (tb[TCA_IPT_INDEX-1] != NULL && | |
121 | RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32)) | |
122 | index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]); | |
123 | ||
e9ce1cd3 DM |
124 | pc = tcf_hash_check(index, a, bind, &ipt_hash_info); |
125 | if (!pc) { | |
126 | pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind, | |
127 | &ipt_idx_gen, &ipt_hash_info); | |
128 | if (unlikely(!pc)) | |
1da177e4 LT |
129 | return -ENOMEM; |
130 | ret = ACT_P_CREATED; | |
131 | } else { | |
132 | if (!ovr) { | |
e9ce1cd3 | 133 | tcf_ipt_release(to_ipt(pc), bind); |
1da177e4 LT |
134 | return -EEXIST; |
135 | } | |
136 | } | |
e9ce1cd3 | 137 | ipt = to_ipt(pc); |
1da177e4 LT |
138 | |
139 | hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]); | |
140 | ||
141 | err = -ENOMEM; | |
142 | tname = kmalloc(IFNAMSIZ, GFP_KERNEL); | |
e9ce1cd3 | 143 | if (unlikely(!tname)) |
1da177e4 LT |
144 | goto err1; |
145 | if (tb[TCA_IPT_TABLE - 1] == NULL || | |
146 | rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ) | |
147 | strcpy(tname, "mangle"); | |
148 | ||
c7b1b249 | 149 | t = kmemdup(td, td->u.target_size, GFP_KERNEL); |
e9ce1cd3 | 150 | if (unlikely(!t)) |
1da177e4 | 151 | goto err2; |
1da177e4 LT |
152 | |
153 | if ((err = ipt_init_target(t, tname, hook)) < 0) | |
154 | goto err3; | |
155 | ||
e9ce1cd3 | 156 | spin_lock_bh(&ipt->tcf_lock); |
1da177e4 | 157 | if (ret != ACT_P_CREATED) { |
e9ce1cd3 DM |
158 | ipt_destroy_target(ipt->tcfi_t); |
159 | kfree(ipt->tcfi_tname); | |
160 | kfree(ipt->tcfi_t); | |
1da177e4 | 161 | } |
e9ce1cd3 DM |
162 | ipt->tcfi_tname = tname; |
163 | ipt->tcfi_t = t; | |
164 | ipt->tcfi_hook = hook; | |
165 | spin_unlock_bh(&ipt->tcf_lock); | |
1da177e4 | 166 | if (ret == ACT_P_CREATED) |
e9ce1cd3 | 167 | tcf_hash_insert(pc, &ipt_hash_info); |
1da177e4 LT |
168 | return ret; |
169 | ||
170 | err3: | |
171 | kfree(t); | |
172 | err2: | |
173 | kfree(tname); | |
174 | err1: | |
e9ce1cd3 | 175 | kfree(pc); |
1da177e4 LT |
176 | return err; |
177 | } | |
178 | ||
e9ce1cd3 | 179 | static int tcf_ipt_cleanup(struct tc_action *a, int bind) |
1da177e4 | 180 | { |
e9ce1cd3 DM |
181 | struct tcf_ipt *ipt = a->priv; |
182 | return tcf_ipt_release(ipt, bind); | |
1da177e4 LT |
183 | } |
184 | ||
e9ce1cd3 DM |
185 | static int tcf_ipt(struct sk_buff *skb, struct tc_action *a, |
186 | struct tcf_result *res) | |
1da177e4 LT |
187 | { |
188 | int ret = 0, result = 0; | |
e9ce1cd3 | 189 | struct tcf_ipt *ipt = a->priv; |
1da177e4 LT |
190 | |
191 | if (skb_cloned(skb)) { | |
192 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) | |
193 | return TC_ACT_UNSPEC; | |
194 | } | |
195 | ||
e9ce1cd3 | 196 | spin_lock(&ipt->tcf_lock); |
1da177e4 | 197 | |
e9ce1cd3 DM |
198 | ipt->tcf_tm.lastuse = jiffies; |
199 | ipt->tcf_bstats.bytes += skb->len; | |
200 | ipt->tcf_bstats.packets++; | |
1da177e4 LT |
201 | |
202 | /* yes, we have to worry about both in and out dev | |
203 | worry later - danger - this API seems to have changed | |
204 | from earlier kernels */ | |
3db05fea | 205 | ret = ipt->tcfi_t->u.kernel.target->target(skb, skb->dev, NULL, |
e9ce1cd3 DM |
206 | ipt->tcfi_hook, |
207 | ipt->tcfi_t->u.kernel.target, | |
fe1cb108 | 208 | ipt->tcfi_t->data); |
1da177e4 LT |
209 | switch (ret) { |
210 | case NF_ACCEPT: | |
211 | result = TC_ACT_OK; | |
212 | break; | |
213 | case NF_DROP: | |
214 | result = TC_ACT_SHOT; | |
e9ce1cd3 | 215 | ipt->tcf_qstats.drops++; |
1da177e4 LT |
216 | break; |
217 | case IPT_CONTINUE: | |
218 | result = TC_ACT_PIPE; | |
219 | break; | |
220 | default: | |
221 | if (net_ratelimit()) | |
222 | printk("Bogus netfilter code %d assume ACCEPT\n", ret); | |
223 | result = TC_POLICE_OK; | |
224 | break; | |
225 | } | |
e9ce1cd3 | 226 | spin_unlock(&ipt->tcf_lock); |
1da177e4 LT |
227 | return result; |
228 | ||
229 | } | |
230 | ||
e9ce1cd3 | 231 | static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) |
1da177e4 | 232 | { |
27a884dc | 233 | unsigned char *b = skb_tail_pointer(skb); |
e9ce1cd3 | 234 | struct tcf_ipt *ipt = a->priv; |
1da177e4 LT |
235 | struct ipt_entry_target *t; |
236 | struct tcf_t tm; | |
237 | struct tc_cnt c; | |
1da177e4 LT |
238 | |
239 | /* for simple targets kernel size == user size | |
240 | ** user name = target name | |
241 | ** for foolproof you need to not assume this | |
242 | */ | |
243 | ||
c7b1b249 | 244 | t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC); |
e9ce1cd3 | 245 | if (unlikely(!t)) |
1da177e4 LT |
246 | goto rtattr_failure; |
247 | ||
e9ce1cd3 DM |
248 | c.bindcnt = ipt->tcf_bindcnt - bind; |
249 | c.refcnt = ipt->tcf_refcnt - ref; | |
e9ce1cd3 DM |
250 | strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name); |
251 | ||
252 | RTA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t); | |
253 | RTA_PUT(skb, TCA_IPT_INDEX, 4, &ipt->tcf_index); | |
254 | RTA_PUT(skb, TCA_IPT_HOOK, 4, &ipt->tcfi_hook); | |
1da177e4 | 255 | RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c); |
e9ce1cd3 DM |
256 | RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, ipt->tcfi_tname); |
257 | tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install); | |
258 | tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse); | |
259 | tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires); | |
1da177e4 LT |
260 | RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm); |
261 | kfree(t); | |
262 | return skb->len; | |
263 | ||
e9ce1cd3 | 264 | rtattr_failure: |
dc5fc579 | 265 | nlmsg_trim(skb, b); |
1da177e4 LT |
266 | kfree(t); |
267 | return -1; | |
268 | } | |
269 | ||
270 | static struct tc_action_ops act_ipt_ops = { | |
271 | .kind = "ipt", | |
e9ce1cd3 | 272 | .hinfo = &ipt_hash_info, |
1da177e4 LT |
273 | .type = TCA_ACT_IPT, |
274 | .capab = TCA_CAP_NONE, | |
275 | .owner = THIS_MODULE, | |
276 | .act = tcf_ipt, | |
277 | .dump = tcf_ipt_dump, | |
278 | .cleanup = tcf_ipt_cleanup, | |
279 | .lookup = tcf_hash_search, | |
280 | .init = tcf_ipt_init, | |
281 | .walk = tcf_generic_walker | |
282 | }; | |
283 | ||
284 | MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); | |
285 | MODULE_DESCRIPTION("Iptables target actions"); | |
286 | MODULE_LICENSE("GPL"); | |
287 | ||
e9ce1cd3 | 288 | static int __init ipt_init_module(void) |
1da177e4 LT |
289 | { |
290 | return tcf_register_action(&act_ipt_ops); | |
291 | } | |
292 | ||
e9ce1cd3 | 293 | static void __exit ipt_cleanup_module(void) |
1da177e4 LT |
294 | { |
295 | tcf_unregister_action(&act_ipt_ops); | |
296 | } | |
297 | ||
298 | module_init(ipt_init_module); | |
299 | module_exit(ipt_cleanup_module); |