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15#include <linux/types.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/skbuff.h>
20#include <linux/rtnetlink.h>
21#include <linux/module.h>
22#include <linux/init.h>
23#include <net/net_namespace.h>
24#include <net/netlink.h>
25#include <net/pkt_sched.h>
26#include <linux/tc_act/tc_mirred.h>
27#include <net/tc_act/tc_mirred.h>
28
29#include <linux/if_arp.h>
30
31#define MIRRED_TAB_MASK 7
32static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
33static u32 mirred_idx_gen;
34static DEFINE_RWLOCK(mirred_lock);
35
36static struct tcf_hashinfo mirred_hash_info = {
37 .htab = tcf_mirred_ht,
38 .hmask = MIRRED_TAB_MASK,
39 .lock = &mirred_lock,
40};
41
42static inline int tcf_mirred_release(struct tcf_mirred *m, int bind)
43{
44 if (m) {
45 if (bind)
46 m->tcf_bindcnt--;
47 m->tcf_refcnt--;
48 if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
49 dev_put(m->tcfm_dev);
50 tcf_hash_destroy(&m->common, &mirred_hash_info);
51 return 1;
52 }
53 }
54 return 0;
55}
56
57static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
58 [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
59};
60
61static int tcf_mirred_init(struct nlattr *nla, struct nlattr *est,
62 struct tc_action *a, int ovr, int bind)
63{
64 struct nlattr *tb[TCA_MIRRED_MAX + 1];
65 struct tc_mirred *parm;
66 struct tcf_mirred *m;
67 struct tcf_common *pc;
68 struct net_device *dev = NULL;
69 int ret = 0, err;
70 int ok_push = 0;
71
72 if (nla == NULL)
73 return -EINVAL;
74
75 err = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
76 if (err < 0)
77 return err;
78
79 if (tb[TCA_MIRRED_PARMS] == NULL)
80 return -EINVAL;
81 parm = nla_data(tb[TCA_MIRRED_PARMS]);
82
83 if (parm->ifindex) {
84 dev = __dev_get_by_index(&init_net, parm->ifindex);
85 if (dev == NULL)
86 return -ENODEV;
87 switch (dev->type) {
88 case ARPHRD_TUNNEL:
89 case ARPHRD_TUNNEL6:
90 case ARPHRD_SIT:
91 case ARPHRD_IPGRE:
92 case ARPHRD_VOID:
93 case ARPHRD_NONE:
94 ok_push = 0;
95 break;
96 default:
97 ok_push = 1;
98 break;
99 }
100 }
101
102 pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
103 if (!pc) {
104 if (!parm->ifindex)
105 return -EINVAL;
106 pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
107 &mirred_idx_gen, &mirred_hash_info);
108 if (IS_ERR(pc))
109 return PTR_ERR(pc);
110 ret = ACT_P_CREATED;
111 } else {
112 if (!ovr) {
113 tcf_mirred_release(to_mirred(pc), bind);
114 return -EEXIST;
115 }
116 }
117 m = to_mirred(pc);
118
119 spin_lock_bh(&m->tcf_lock);
120 m->tcf_action = parm->action;
121 m->tcfm_eaction = parm->eaction;
122 if (parm->ifindex) {
123 m->tcfm_ifindex = parm->ifindex;
124 if (ret != ACT_P_CREATED)
125 dev_put(m->tcfm_dev);
126 m->tcfm_dev = dev;
127 dev_hold(dev);
128 m->tcfm_ok_push = ok_push;
129 }
130 spin_unlock_bh(&m->tcf_lock);
131 if (ret == ACT_P_CREATED)
132 tcf_hash_insert(pc, &mirred_hash_info);
133
134 return ret;
135}
136
137static int tcf_mirred_cleanup(struct tc_action *a, int bind)
138{
139 struct tcf_mirred *m = a->priv;
140
141 if (m)
142 return tcf_mirred_release(m, bind);
143 return 0;
144}
145
146static int tcf_mirred(struct sk_buff *skb, struct tc_action *a,
147 struct tcf_result *res)
148{
149 struct tcf_mirred *m = a->priv;
150 struct net_device *dev;
151 struct sk_buff *skb2 = NULL;
152 u32 at = G_TC_AT(skb->tc_verd);
153
154 spin_lock(&m->tcf_lock);
155
156 dev = m->tcfm_dev;
157 m->tcf_tm.lastuse = jiffies;
158
159 if (!(dev->flags&IFF_UP) ) {
160 if (net_ratelimit())
161 printk("mirred to Houston: device %s is gone!\n",
162 dev->name);
163bad_mirred:
164 if (skb2 != NULL)
165 kfree_skb(skb2);
166 m->tcf_qstats.overlimits++;
167 m->tcf_bstats.bytes += qdisc_pkt_len(skb);
168 m->tcf_bstats.packets++;
169 spin_unlock(&m->tcf_lock);
170
171
172
173 return TC_ACT_SHOT;
174 }
175
176 skb2 = skb_act_clone(skb, GFP_ATOMIC);
177 if (skb2 == NULL)
178 goto bad_mirred;
179 if (m->tcfm_eaction != TCA_EGRESS_MIRROR &&
180 m->tcfm_eaction != TCA_EGRESS_REDIR) {
181 if (net_ratelimit())
182 printk("tcf_mirred unknown action %d\n",
183 m->tcfm_eaction);
184 goto bad_mirred;
185 }
186
187 m->tcf_bstats.bytes += qdisc_pkt_len(skb2);
188 m->tcf_bstats.packets++;
189 if (!(at & AT_EGRESS))
190 if (m->tcfm_ok_push)
191 skb_push(skb2, skb2->dev->hard_header_len);
192
193
194 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
195 skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
196
197 skb2->dev = dev;
198 skb2->iif = skb->dev->ifindex;
199 dev_queue_xmit(skb2);
200 spin_unlock(&m->tcf_lock);
201 return m->tcf_action;
202}
203
204static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
205{
206 unsigned char *b = skb_tail_pointer(skb);
207 struct tcf_mirred *m = a->priv;
208 struct tc_mirred opt;
209 struct tcf_t t;
210
211 opt.index = m->tcf_index;
212 opt.action = m->tcf_action;
213 opt.refcnt = m->tcf_refcnt - ref;
214 opt.bindcnt = m->tcf_bindcnt - bind;
215 opt.eaction = m->tcfm_eaction;
216 opt.ifindex = m->tcfm_ifindex;
217 NLA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
218 t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
219 t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
220 t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
221 NLA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
222 return skb->len;
223
224nla_put_failure:
225 nlmsg_trim(skb, b);
226 return -1;
227}
228
229static struct tc_action_ops act_mirred_ops = {
230 .kind = "mirred",
231 .hinfo = &mirred_hash_info,
232 .type = TCA_ACT_MIRRED,
233 .capab = TCA_CAP_NONE,
234 .owner = THIS_MODULE,
235 .act = tcf_mirred,
236 .dump = tcf_mirred_dump,
237 .cleanup = tcf_mirred_cleanup,
238 .lookup = tcf_hash_search,
239 .init = tcf_mirred_init,
240 .walk = tcf_generic_walker
241};
242
243MODULE_AUTHOR("Jamal Hadi Salim(2002)");
244MODULE_DESCRIPTION("Device Mirror/redirect actions");
245MODULE_LICENSE("GPL");
246
247static int __init mirred_init_module(void)
248{
249 printk("Mirror/redirect action on\n");
250 return tcf_register_action(&act_mirred_ops);
251}
252
253static void __exit mirred_cleanup_module(void)
254{
255 tcf_unregister_action(&act_mirred_ops);
256}
257
258module_init(mirred_init_module);
259module_exit(mirred_cleanup_module);
260
