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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 <linux/slab.h>
23#include <net/netlink.h>
24#include <net/pkt_sched.h>
25#include <linux/tc_act/tc_ipt.h>
26#include <net/tc_act/tc_ipt.h>
27
28#include <linux/netfilter_ipv4/ip_tables.h>
29
30
31#define IPT_TAB_MASK 15
32static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
33static u32 ipt_idx_gen;
34static DEFINE_RWLOCK(ipt_lock);
35
36static struct tcf_hashinfo ipt_hash_info = {
37 .htab = tcf_ipt_ht,
38 .hmask = IPT_TAB_MASK,
39 .lock = &ipt_lock,
40};
41
42static int ipt_init_target(struct xt_entry_target *t, char *table, unsigned int hook)
43{
44 struct xt_tgchk_param par;
45 struct xt_target *target;
46 int ret = 0;
47
48 target = xt_request_find_target(AF_INET, t->u.user.name,
49 t->u.user.revision);
50 if (IS_ERR(target))
51 return PTR_ERR(target);
52
53 t->u.kernel.target = target;
54 par.table = table;
55 par.entryinfo = NULL;
56 par.target = target;
57 par.targinfo = t->data;
58 par.hook_mask = hook;
59 par.family = NFPROTO_IPV4;
60
61 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
62 if (ret < 0) {
63 module_put(t->u.kernel.target->me);
64 return ret;
65 }
66 return 0;
67}
68
69static void ipt_destroy_target(struct xt_entry_target *t)
70{
71 struct xt_tgdtor_param par = {
72 .target = t->u.kernel.target,
73 .targinfo = t->data,
74 };
75 if (par.target->destroy != NULL)
76 par.target->destroy(&par);
77 module_put(par.target->me);
78}
79
80static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
81{
82 int ret = 0;
83 if (ipt) {
84 if (bind)
85 ipt->tcf_bindcnt--;
86 ipt->tcf_refcnt--;
87 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
88 ipt_destroy_target(ipt->tcfi_t);
89 kfree(ipt->tcfi_tname);
90 kfree(ipt->tcfi_t);
91 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
92 ret = ACT_P_DELETED;
93 }
94 }
95 return ret;
96}
97
98static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
99 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
100 [TCA_IPT_HOOK] = { .type = NLA_U32 },
101 [TCA_IPT_INDEX] = { .type = NLA_U32 },
102 [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
103};
104
105static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est,
106 struct tc_action *a, int ovr, int bind)
107{
108 struct nlattr *tb[TCA_IPT_MAX + 1];
109 struct tcf_ipt *ipt;
110 struct tcf_common *pc;
111 struct xt_entry_target *td, *t;
112 char *tname;
113 int ret = 0, err;
114 u32 hook = 0;
115 u32 index = 0;
116
117 if (nla == NULL)
118 return -EINVAL;
119
120 err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
121 if (err < 0)
122 return err;
123
124 if (tb[TCA_IPT_HOOK] == NULL)
125 return -EINVAL;
126 if (tb[TCA_IPT_TARG] == NULL)
127 return -EINVAL;
128
129 td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
130 if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
131 return -EINVAL;
132
133 if (tb[TCA_IPT_INDEX] != NULL)
134 index = nla_get_u32(tb[TCA_IPT_INDEX]);
135
136 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
137 if (!pc) {
138 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
139 &ipt_idx_gen, &ipt_hash_info);
140 if (IS_ERR(pc))
141 return PTR_ERR(pc);
142 ret = ACT_P_CREATED;
143 } else {
144 if (!ovr) {
145 tcf_ipt_release(to_ipt(pc), bind);
146 return -EEXIST;
147 }
148 }
149 ipt = to_ipt(pc);
150
151 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
152
153 err = -ENOMEM;
154 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
155 if (unlikely(!tname))
156 goto err1;
157 if (tb[TCA_IPT_TABLE] == NULL ||
158 nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
159 strcpy(tname, "mangle");
160
161 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
162 if (unlikely(!t))
163 goto err2;
164
165 err = ipt_init_target(t, tname, hook);
166 if (err < 0)
167 goto err3;
168
169 spin_lock_bh(&ipt->tcf_lock);
170 if (ret != ACT_P_CREATED) {
171 ipt_destroy_target(ipt->tcfi_t);
172 kfree(ipt->tcfi_tname);
173 kfree(ipt->tcfi_t);
174 }
175 ipt->tcfi_tname = tname;
176 ipt->tcfi_t = t;
177 ipt->tcfi_hook = hook;
178 spin_unlock_bh(&ipt->tcf_lock);
179 if (ret == ACT_P_CREATED)
180 tcf_hash_insert(pc, &ipt_hash_info);
181 return ret;
182
183err3:
184 kfree(t);
185err2:
186 kfree(tname);
187err1:
188 kfree(pc);
189 return err;
190}
191
192static int tcf_ipt_cleanup(struct tc_action *a, int bind)
193{
194 struct tcf_ipt *ipt = a->priv;
195 return tcf_ipt_release(ipt, bind);
196}
197
198static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a,
199 struct tcf_result *res)
200{
201 int ret = 0, result = 0;
202 struct tcf_ipt *ipt = a->priv;
203 struct xt_action_param par;
204
205 if (skb_cloned(skb)) {
206 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
207 return TC_ACT_UNSPEC;
208 }
209
210 spin_lock(&ipt->tcf_lock);
211
212 ipt->tcf_tm.lastuse = jiffies;
213 bstats_update(&ipt->tcf_bstats, skb);
214
215
216
217
218
219 par.in = skb->dev;
220 par.out = NULL;
221 par.hooknum = ipt->tcfi_hook;
222 par.target = ipt->tcfi_t->u.kernel.target;
223 par.targinfo = ipt->tcfi_t->data;
224 ret = par.target->target(skb, &par);
225
226 switch (ret) {
227 case NF_ACCEPT:
228 result = TC_ACT_OK;
229 break;
230 case NF_DROP:
231 result = TC_ACT_SHOT;
232 ipt->tcf_qstats.drops++;
233 break;
234 case XT_CONTINUE:
235 result = TC_ACT_PIPE;
236 break;
237 default:
238 if (net_ratelimit())
239 pr_notice("tc filter: Bogus netfilter code"
240 " %d assume ACCEPT\n", ret);
241 result = TC_POLICE_OK;
242 break;
243 }
244 spin_unlock(&ipt->tcf_lock);
245 return result;
246
247}
248
249static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
250{
251 unsigned char *b = skb_tail_pointer(skb);
252 struct tcf_ipt *ipt = a->priv;
253 struct xt_entry_target *t;
254 struct tcf_t tm;
255 struct tc_cnt c;
256
257
258
259
260
261
262 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
263 if (unlikely(!t))
264 goto nla_put_failure;
265
266 c.bindcnt = ipt->tcf_bindcnt - bind;
267 c.refcnt = ipt->tcf_refcnt - ref;
268 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
269
270 NLA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
271 NLA_PUT_U32(skb, TCA_IPT_INDEX, ipt->tcf_index);
272 NLA_PUT_U32(skb, TCA_IPT_HOOK, ipt->tcfi_hook);
273 NLA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
274 NLA_PUT_STRING(skb, TCA_IPT_TABLE, ipt->tcfi_tname);
275 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
276 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
277 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
278 NLA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
279 kfree(t);
280 return skb->len;
281
282nla_put_failure:
283 nlmsg_trim(skb, b);
284 kfree(t);
285 return -1;
286}
287
288static struct tc_action_ops act_ipt_ops = {
289 .kind = "ipt",
290 .hinfo = &ipt_hash_info,
291 .type = TCA_ACT_IPT,
292 .capab = TCA_CAP_NONE,
293 .owner = THIS_MODULE,
294 .act = tcf_ipt,
295 .dump = tcf_ipt_dump,
296 .cleanup = tcf_ipt_cleanup,
297 .lookup = tcf_hash_search,
298 .init = tcf_ipt_init,
299 .walk = tcf_generic_walker
300};
301
302MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
303MODULE_DESCRIPTION("Iptables target actions");
304MODULE_LICENSE("GPL");
305
306static int __init ipt_init_module(void)
307{
308 return tcf_register_action(&act_ipt_ops);
309}
310
311static void __exit ipt_cleanup_module(void)
312{
313 tcf_unregister_action(&act_ipt_ops);
314}
315
316module_init(ipt_init_module);
317module_exit(ipt_cleanup_module);
318
