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14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/skbuff.h>
19#include <linux/rtnetlink.h>
20#include <linux/module.h>
21#include <linux/init.h>
22#include <net/netlink.h>
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
29
30#define IPT_TAB_MASK 15
31static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
32static u32 ipt_idx_gen;
33static DEFINE_RWLOCK(ipt_lock);
34
35static struct tcf_hashinfo ipt_hash_info = {
36 .htab = tcf_ipt_ht,
37 .hmask = IPT_TAB_MASK,
38 .lock = &ipt_lock,
39};
40
41static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
42{
43 struct xt_target *target;
44 int ret = 0;
45
46 target = xt_request_find_target(AF_INET, t->u.user.name,
47 t->u.user.revision);
48 if (!target)
49 return -ENOENT;
50
51 t->u.kernel.target = target;
52
53 ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
54 table, hook, 0, 0);
55 if (ret) {
56 module_put(t->u.kernel.target->me);
57 return ret;
58 }
59 if (t->u.kernel.target->checkentry
60 && !t->u.kernel.target->checkentry(table, NULL,
61 t->u.kernel.target, t->data,
62 hook)) {
63 module_put(t->u.kernel.target->me);
64 ret = -EINVAL;
65 }
66
67 return ret;
68}
69
70static void ipt_destroy_target(struct ipt_entry_target *t)
71{
72 if (t->u.kernel.target->destroy)
73 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
74 module_put(t->u.kernel.target->me);
75}
76
77static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
78{
79 int ret = 0;
80 if (ipt) {
81 if (bind)
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);
89 ret = ACT_P_DELETED;
90 }
91 }
92 return ret;
93}
94
95static int tcf_ipt_init(struct rtattr *rta, struct rtattr *est,
96 struct tc_action *a, int ovr, int bind)
97{
98 struct rtattr *tb[TCA_IPT_MAX];
99 struct tcf_ipt *ipt;
100 struct tcf_common *pc;
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
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))
129 return -ENOMEM;
130 ret = ACT_P_CREATED;
131 } else {
132 if (!ovr) {
133 tcf_ipt_release(to_ipt(pc), bind);
134 return -EEXIST;
135 }
136 }
137 ipt = to_ipt(pc);
138
139 hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
140
141 err = -ENOMEM;
142 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
143 if (unlikely(!tname))
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
149 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
150 if (unlikely(!t))
151 goto err2;
152
153 if ((err = ipt_init_target(t, tname, hook)) < 0)
154 goto err3;
155
156 spin_lock_bh(&ipt->tcf_lock);
157 if (ret != ACT_P_CREATED) {
158 ipt_destroy_target(ipt->tcfi_t);
159 kfree(ipt->tcfi_tname);
160 kfree(ipt->tcfi_t);
161 }
162 ipt->tcfi_tname = tname;
163 ipt->tcfi_t = t;
164 ipt->tcfi_hook = hook;
165 spin_unlock_bh(&ipt->tcf_lock);
166 if (ret == ACT_P_CREATED)
167 tcf_hash_insert(pc, &ipt_hash_info);
168 return ret;
169
170err3:
171 kfree(t);
172err2:
173 kfree(tname);
174err1:
175 kfree(pc);
176 return err;
177}
178
179static int tcf_ipt_cleanup(struct tc_action *a, int bind)
180{
181 struct tcf_ipt *ipt = a->priv;
182 return tcf_ipt_release(ipt, bind);
183}
184
185static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
186 struct tcf_result *res)
187{
188 int ret = 0, result = 0;
189 struct tcf_ipt *ipt = a->priv;
190
191 if (skb_cloned(skb)) {
192 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
193 return TC_ACT_UNSPEC;
194 }
195
196 spin_lock(&ipt->tcf_lock);
197
198 ipt->tcf_tm.lastuse = jiffies;
199 ipt->tcf_bstats.bytes += skb->len;
200 ipt->tcf_bstats.packets++;
201
202
203
204
205 ret = ipt->tcfi_t->u.kernel.target->target(skb, skb->dev, NULL,
206 ipt->tcfi_hook,
207 ipt->tcfi_t->u.kernel.target,
208 ipt->tcfi_t->data);
209 switch (ret) {
210 case NF_ACCEPT:
211 result = TC_ACT_OK;
212 break;
213 case NF_DROP:
214 result = TC_ACT_SHOT;
215 ipt->tcf_qstats.drops++;
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 }
226 spin_unlock(&ipt->tcf_lock);
227 return result;
228
229}
230
231static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
232{
233 unsigned char *b = skb_tail_pointer(skb);
234 struct tcf_ipt *ipt = a->priv;
235 struct ipt_entry_target *t;
236 struct tcf_t tm;
237 struct tc_cnt c;
238
239
240
241
242
243
244 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
245 if (unlikely(!t))
246 goto rtattr_failure;
247
248 c.bindcnt = ipt->tcf_bindcnt - bind;
249 c.refcnt = ipt->tcf_refcnt - ref;
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);
255 RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
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);
260 RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
261 kfree(t);
262 return skb->len;
263
264rtattr_failure:
265 nlmsg_trim(skb, b);
266 kfree(t);
267 return -1;
268}
269
270static struct tc_action_ops act_ipt_ops = {
271 .kind = "ipt",
272 .hinfo = &ipt_hash_info,
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
284MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
285MODULE_DESCRIPTION("Iptables target actions");
286MODULE_LICENSE("GPL");
287
288static int __init ipt_init_module(void)
289{
290 return tcf_register_action(&act_ipt_ops);
291}
292
293static void __exit ipt_cleanup_module(void)
294{
295 tcf_unregister_action(&act_ipt_ops);
296}
297
298module_init(ipt_init_module);
299module_exit(ipt_cleanup_module);
300
