2 * net/sched/mirred.c packet mirroring and redirect actions
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Jamal Hadi Salim (2002-4)
11 * TODO: Add ingress support (and socket redirect support)
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 <linux/gfp.h>
24 #include <net/net_namespace.h>
25 #include <net/netlink.h>
26 #include <net/pkt_sched.h>
27 #include <linux/tc_act/tc_mirred.h>
28 #include <net/tc_act/tc_mirred.h>
30 #include <linux/if_arp.h>
32 #define MIRRED_TAB_MASK 7
33 static LIST_HEAD(mirred_list);
34 static struct tcf_hashinfo mirred_hash_info;
36 static int tcf_mirred_release(struct tcf_mirred *m, int bind)
42 if (!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
43 list_del(&m->tcfm_list);
46 tcf_hash_destroy(&m->common, &mirred_hash_info);
53 static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
54 [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
57 static int tcf_mirred_init(struct net *net, struct nlattr *nla,
58 struct nlattr *est, struct tc_action *a, int ovr,
61 struct nlattr *tb[TCA_MIRRED_MAX + 1];
62 struct tc_mirred *parm;
64 struct tcf_common *pc;
65 struct net_device *dev;
70 ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
73 if (tb[TCA_MIRRED_PARMS] == NULL)
75 parm = nla_data(tb[TCA_MIRRED_PARMS]);
76 switch (parm->eaction) {
77 case TCA_EGRESS_MIRROR:
78 case TCA_EGRESS_REDIR:
84 dev = __dev_get_by_index(net, parm->ifindex);
104 pc = tcf_hash_check(parm->index, a, bind);
108 pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind);
114 tcf_mirred_release(to_mirred(pc), bind);
120 spin_lock_bh(&m->tcf_lock);
121 m->tcf_action = parm->action;
122 m->tcfm_eaction = parm->eaction;
124 m->tcfm_ifindex = parm->ifindex;
125 if (ret != ACT_P_CREATED)
126 dev_put(m->tcfm_dev);
129 m->tcfm_ok_push = ok_push;
131 spin_unlock_bh(&m->tcf_lock);
132 if (ret == ACT_P_CREATED) {
133 list_add(&m->tcfm_list, &mirred_list);
134 tcf_hash_insert(pc, a->ops->hinfo);
140 static int tcf_mirred_cleanup(struct tc_action *a, int bind)
142 struct tcf_mirred *m = a->priv;
145 return tcf_mirred_release(m, bind);
149 static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
150 struct tcf_result *res)
152 struct tcf_mirred *m = a->priv;
153 struct net_device *dev;
154 struct sk_buff *skb2;
158 spin_lock(&m->tcf_lock);
159 m->tcf_tm.lastuse = jiffies;
160 bstats_update(&m->tcf_bstats, skb);
164 printk_once(KERN_NOTICE "tc mirred: target device is gone\n");
168 if (!(dev->flags & IFF_UP)) {
169 net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
174 at = G_TC_AT(skb->tc_verd);
175 skb2 = skb_act_clone(skb, GFP_ATOMIC, m->tcf_action);
179 if (!(at & AT_EGRESS)) {
181 skb_push(skb2, skb2->dev->hard_header_len);
184 /* mirror is always swallowed */
185 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
186 skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
188 skb2->skb_iif = skb->dev->ifindex;
190 err = dev_queue_xmit(skb2);
194 m->tcf_qstats.overlimits++;
195 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
196 retval = TC_ACT_SHOT;
198 retval = m->tcf_action;
200 retval = m->tcf_action;
201 spin_unlock(&m->tcf_lock);
206 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
208 unsigned char *b = skb_tail_pointer(skb);
209 struct tcf_mirred *m = a->priv;
210 struct tc_mirred opt = {
211 .index = m->tcf_index,
212 .action = m->tcf_action,
213 .refcnt = m->tcf_refcnt - ref,
214 .bindcnt = m->tcf_bindcnt - bind,
215 .eaction = m->tcfm_eaction,
216 .ifindex = m->tcfm_ifindex,
220 if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
221 goto nla_put_failure;
222 t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
223 t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
224 t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
225 if (nla_put(skb, TCA_MIRRED_TM, sizeof(t), &t))
226 goto nla_put_failure;
234 static int mirred_device_event(struct notifier_block *unused,
235 unsigned long event, void *ptr)
237 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
238 struct tcf_mirred *m;
240 if (event == NETDEV_UNREGISTER)
241 list_for_each_entry(m, &mirred_list, tcfm_list) {
242 if (m->tcfm_dev == dev) {
251 static struct notifier_block mirred_device_notifier = {
252 .notifier_call = mirred_device_event,
255 static struct tc_action_ops act_mirred_ops = {
257 .hinfo = &mirred_hash_info,
258 .type = TCA_ACT_MIRRED,
259 .owner = THIS_MODULE,
261 .dump = tcf_mirred_dump,
262 .cleanup = tcf_mirred_cleanup,
263 .init = tcf_mirred_init,
266 MODULE_AUTHOR("Jamal Hadi Salim(2002)");
267 MODULE_DESCRIPTION("Device Mirror/redirect actions");
268 MODULE_LICENSE("GPL");
270 static int __init mirred_init_module(void)
272 int err = register_netdevice_notifier(&mirred_device_notifier);
276 err = tcf_hashinfo_init(&mirred_hash_info, MIRRED_TAB_MASK);
278 unregister_netdevice_notifier(&mirred_device_notifier);
281 pr_info("Mirror/redirect action on\n");
282 return tcf_register_action(&act_mirred_ops);
285 static void __exit mirred_cleanup_module(void)
287 tcf_unregister_action(&act_mirred_ops);
288 tcf_hashinfo_destroy(&mirred_hash_info);
289 unregister_netdevice_notifier(&mirred_device_notifier);
292 module_init(mirred_init_module);
293 module_exit(mirred_cleanup_module);