]>
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> | |
17 | #include <linux/config.h> | |
18 | #include <linux/types.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/sched.h> | |
21 | #include <linux/string.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/socket.h> | |
24 | #include <linux/sockios.h> | |
25 | #include <linux/in.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/netdevice.h> | |
29 | #include <linux/skbuff.h> | |
30 | #include <linux/rtnetlink.h> | |
31 | #include <linux/module.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/proc_fs.h> | |
34 | #include <linux/kmod.h> | |
35 | #include <net/sock.h> | |
36 | #include <net/pkt_sched.h> | |
37 | #include <linux/tc_act/tc_ipt.h> | |
38 | #include <net/tc_act/tc_ipt.h> | |
39 | ||
40 | #include <linux/netfilter_ipv4/ip_tables.h> | |
41 | ||
42 | /* use generic hash table */ | |
43 | #define MY_TAB_SIZE 16 | |
44 | #define MY_TAB_MASK 15 | |
45 | ||
46 | static u32 idx_gen; | |
47 | static struct tcf_ipt *tcf_ipt_ht[MY_TAB_SIZE]; | |
48 | /* ipt hash table lock */ | |
49 | static DEFINE_RWLOCK(ipt_lock); | |
50 | ||
51 | /* ovewrride the defaults */ | |
52 | #define tcf_st tcf_ipt | |
53 | #define tcf_t_lock ipt_lock | |
54 | #define tcf_ht tcf_ipt_ht | |
55 | ||
56 | #define CONFIG_NET_ACT_INIT | |
57 | #include <net/pkt_act.h> | |
58 | ||
59 | static int | |
60 | ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook) | |
61 | { | |
62 | struct ipt_target *target; | |
63 | int ret = 0; | |
64 | ||
65 | target = ipt_find_target(t->u.user.name, t->u.user.revision); | |
66 | if (!target) | |
67 | return -ENOENT; | |
68 | ||
69 | DPRINTK("ipt_init_target: found %s\n", target->name); | |
70 | t->u.kernel.target = target; | |
71 | ||
72 | if (t->u.kernel.target->checkentry | |
73 | && !t->u.kernel.target->checkentry(table, NULL, t->data, | |
74 | t->u.target_size - sizeof(*t), | |
75 | hook)) { | |
76 | DPRINTK("ipt_init_target: check failed for `%s'.\n", | |
77 | t->u.kernel.target->name); | |
78 | module_put(t->u.kernel.target->me); | |
79 | ret = -EINVAL; | |
80 | } | |
81 | ||
82 | return ret; | |
83 | } | |
84 | ||
85 | static void | |
86 | ipt_destroy_target(struct ipt_entry_target *t) | |
87 | { | |
88 | if (t->u.kernel.target->destroy) | |
89 | t->u.kernel.target->destroy(t->data, | |
90 | t->u.target_size - sizeof(*t)); | |
91 | module_put(t->u.kernel.target->me); | |
92 | } | |
93 | ||
94 | static int | |
95 | tcf_ipt_release(struct tcf_ipt *p, int bind) | |
96 | { | |
97 | int ret = 0; | |
98 | if (p) { | |
99 | if (bind) | |
100 | p->bindcnt--; | |
101 | p->refcnt--; | |
102 | if (p->bindcnt <= 0 && p->refcnt <= 0) { | |
103 | ipt_destroy_target(p->t); | |
104 | kfree(p->tname); | |
105 | kfree(p->t); | |
106 | tcf_hash_destroy(p); | |
107 | ret = ACT_P_DELETED; | |
108 | } | |
109 | } | |
110 | return ret; | |
111 | } | |
112 | ||
113 | static int | |
114 | tcf_ipt_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a, | |
115 | int ovr, int bind) | |
116 | { | |
117 | struct rtattr *tb[TCA_IPT_MAX]; | |
118 | struct tcf_ipt *p; | |
119 | struct ipt_entry_target *td, *t; | |
120 | char *tname; | |
121 | int ret = 0, err; | |
122 | u32 hook = 0; | |
123 | u32 index = 0; | |
124 | ||
125 | if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0) | |
126 | return -EINVAL; | |
127 | ||
128 | if (tb[TCA_IPT_HOOK-1] == NULL || | |
129 | RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32)) | |
130 | return -EINVAL; | |
131 | if (tb[TCA_IPT_TARG-1] == NULL || | |
132 | RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t)) | |
133 | return -EINVAL; | |
134 | td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]); | |
135 | if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size) | |
136 | return -EINVAL; | |
137 | ||
138 | if (tb[TCA_IPT_INDEX-1] != NULL && | |
139 | RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32)) | |
140 | index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]); | |
141 | ||
142 | p = tcf_hash_check(index, a, ovr, bind); | |
143 | if (p == NULL) { | |
144 | p = tcf_hash_create(index, est, a, sizeof(*p), ovr, bind); | |
145 | if (p == NULL) | |
146 | return -ENOMEM; | |
147 | ret = ACT_P_CREATED; | |
148 | } else { | |
149 | if (!ovr) { | |
150 | tcf_ipt_release(p, bind); | |
151 | return -EEXIST; | |
152 | } | |
153 | } | |
154 | ||
155 | hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]); | |
156 | ||
157 | err = -ENOMEM; | |
158 | tname = kmalloc(IFNAMSIZ, GFP_KERNEL); | |
159 | if (tname == NULL) | |
160 | goto err1; | |
161 | if (tb[TCA_IPT_TABLE - 1] == NULL || | |
162 | rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ) | |
163 | strcpy(tname, "mangle"); | |
164 | ||
165 | t = kmalloc(td->u.target_size, GFP_KERNEL); | |
166 | if (t == NULL) | |
167 | goto err2; | |
168 | memcpy(t, td, td->u.target_size); | |
169 | ||
170 | if ((err = ipt_init_target(t, tname, hook)) < 0) | |
171 | goto err3; | |
172 | ||
173 | spin_lock_bh(&p->lock); | |
174 | if (ret != ACT_P_CREATED) { | |
175 | ipt_destroy_target(p->t); | |
176 | kfree(p->tname); | |
177 | kfree(p->t); | |
178 | } | |
179 | p->tname = tname; | |
180 | p->t = t; | |
181 | p->hook = hook; | |
182 | spin_unlock_bh(&p->lock); | |
183 | if (ret == ACT_P_CREATED) | |
184 | tcf_hash_insert(p); | |
185 | return ret; | |
186 | ||
187 | err3: | |
188 | kfree(t); | |
189 | err2: | |
190 | kfree(tname); | |
191 | err1: | |
192 | kfree(p); | |
193 | return err; | |
194 | } | |
195 | ||
196 | static int | |
197 | tcf_ipt_cleanup(struct tc_action *a, int bind) | |
198 | { | |
199 | struct tcf_ipt *p = PRIV(a, ipt); | |
200 | return tcf_ipt_release(p, bind); | |
201 | } | |
202 | ||
203 | static int | |
204 | tcf_ipt(struct sk_buff **pskb, struct tc_action *a) | |
205 | { | |
206 | int ret = 0, result = 0; | |
207 | struct tcf_ipt *p = PRIV(a, ipt); | |
208 | struct sk_buff *skb = *pskb; | |
209 | ||
210 | if (skb_cloned(skb)) { | |
211 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) | |
212 | return TC_ACT_UNSPEC; | |
213 | } | |
214 | ||
215 | spin_lock(&p->lock); | |
216 | ||
217 | p->tm.lastuse = jiffies; | |
218 | p->bstats.bytes += skb->len; | |
219 | p->bstats.packets++; | |
220 | ||
221 | /* yes, we have to worry about both in and out dev | |
222 | worry later - danger - this API seems to have changed | |
223 | from earlier kernels */ | |
224 | ||
225 | ret = p->t->u.kernel.target->target(&skb, skb->dev, NULL, | |
226 | p->hook, p->t->data, NULL); | |
227 | switch (ret) { | |
228 | case NF_ACCEPT: | |
229 | result = TC_ACT_OK; | |
230 | break; | |
231 | case NF_DROP: | |
232 | result = TC_ACT_SHOT; | |
233 | p->qstats.drops++; | |
234 | break; | |
235 | case IPT_CONTINUE: | |
236 | result = TC_ACT_PIPE; | |
237 | break; | |
238 | default: | |
239 | if (net_ratelimit()) | |
240 | printk("Bogus netfilter code %d assume ACCEPT\n", ret); | |
241 | result = TC_POLICE_OK; | |
242 | break; | |
243 | } | |
244 | spin_unlock(&p->lock); | |
245 | return result; | |
246 | ||
247 | } | |
248 | ||
249 | static int | |
250 | tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) | |
251 | { | |
252 | struct ipt_entry_target *t; | |
253 | struct tcf_t tm; | |
254 | struct tc_cnt c; | |
255 | unsigned char *b = skb->tail; | |
256 | struct tcf_ipt *p = PRIV(a, ipt); | |
257 | ||
258 | /* for simple targets kernel size == user size | |
259 | ** user name = target name | |
260 | ** for foolproof you need to not assume this | |
261 | */ | |
262 | ||
263 | t = kmalloc(p->t->u.user.target_size, GFP_ATOMIC); | |
264 | if (t == NULL) | |
265 | goto rtattr_failure; | |
266 | ||
267 | c.bindcnt = p->bindcnt - bind; | |
268 | c.refcnt = p->refcnt - ref; | |
269 | memcpy(t, p->t, p->t->u.user.target_size); | |
270 | strcpy(t->u.user.name, p->t->u.kernel.target->name); | |
271 | ||
272 | DPRINTK("\ttcf_ipt_dump tablename %s length %d\n", p->tname, | |
273 | strlen(p->tname)); | |
274 | DPRINTK("\tdump target name %s size %d size user %d " | |
275 | "data[0] %x data[1] %x\n", p->t->u.kernel.target->name, | |
276 | p->t->u.target_size, p->t->u.user.target_size, | |
277 | p->t->data[0], p->t->data[1]); | |
278 | RTA_PUT(skb, TCA_IPT_TARG, p->t->u.user.target_size, t); | |
279 | RTA_PUT(skb, TCA_IPT_INDEX, 4, &p->index); | |
280 | RTA_PUT(skb, TCA_IPT_HOOK, 4, &p->hook); | |
281 | RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c); | |
282 | RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, p->tname); | |
283 | tm.install = jiffies_to_clock_t(jiffies - p->tm.install); | |
284 | tm.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse); | |
285 | tm.expires = jiffies_to_clock_t(p->tm.expires); | |
286 | RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm); | |
287 | kfree(t); | |
288 | return skb->len; | |
289 | ||
290 | rtattr_failure: | |
291 | skb_trim(skb, b - skb->data); | |
292 | kfree(t); | |
293 | return -1; | |
294 | } | |
295 | ||
296 | static struct tc_action_ops act_ipt_ops = { | |
297 | .kind = "ipt", | |
298 | .type = TCA_ACT_IPT, | |
299 | .capab = TCA_CAP_NONE, | |
300 | .owner = THIS_MODULE, | |
301 | .act = tcf_ipt, | |
302 | .dump = tcf_ipt_dump, | |
303 | .cleanup = tcf_ipt_cleanup, | |
304 | .lookup = tcf_hash_search, | |
305 | .init = tcf_ipt_init, | |
306 | .walk = tcf_generic_walker | |
307 | }; | |
308 | ||
309 | MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); | |
310 | MODULE_DESCRIPTION("Iptables target actions"); | |
311 | MODULE_LICENSE("GPL"); | |
312 | ||
313 | static int __init | |
314 | ipt_init_module(void) | |
315 | { | |
316 | return tcf_register_action(&act_ipt_ops); | |
317 | } | |
318 | ||
319 | static void __exit | |
320 | ipt_cleanup_module(void) | |
321 | { | |
322 | tcf_unregister_action(&act_ipt_ops); | |
323 | } | |
324 | ||
325 | module_init(ipt_init_module); | |
326 | module_exit(ipt_cleanup_module); |