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 u32 mirred_idx_gen;
34 static LIST_HEAD(mirred_list);
35 static struct tcf_hashinfo mirred_hash_info;
37 static int tcf_mirred_release(struct tcf_mirred *m, int bind)
43 if (!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
44 list_del(&m->tcfm_list);
47 tcf_hash_destroy(&m->common, &mirred_hash_info);
54 static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
55 [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
58 static int tcf_mirred_init(struct net *net, struct nlattr *nla,
59 struct nlattr *est, struct tc_action *a, int ovr,
62 struct nlattr *tb[TCA_MIRRED_MAX + 1];
63 struct tc_mirred *parm;
65 struct tcf_common *pc;
66 struct net_device *dev;
71 ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
74 if (tb[TCA_MIRRED_PARMS] == NULL)
76 parm = nla_data(tb[TCA_MIRRED_PARMS]);
77 switch (parm->eaction) {
78 case TCA_EGRESS_MIRROR:
79 case TCA_EGRESS_REDIR:
85 dev = __dev_get_by_index(net, parm->ifindex);
105 pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
109 pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
110 &mirred_idx_gen, &mirred_hash_info);
116 tcf_mirred_release(to_mirred(pc), bind);
122 spin_lock_bh(&m->tcf_lock);
123 m->tcf_action = parm->action;
124 m->tcfm_eaction = parm->eaction;
126 m->tcfm_ifindex = parm->ifindex;
127 if (ret != ACT_P_CREATED)
128 dev_put(m->tcfm_dev);
131 m->tcfm_ok_push = ok_push;
133 spin_unlock_bh(&m->tcf_lock);
134 if (ret == ACT_P_CREATED) {
135 list_add(&m->tcfm_list, &mirred_list);
136 tcf_hash_insert(pc, &mirred_hash_info);
142 static int tcf_mirred_cleanup(struct tc_action *a, int bind)
144 struct tcf_mirred *m = a->priv;
147 return tcf_mirred_release(m, bind);
151 static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
152 struct tcf_result *res)
154 struct tcf_mirred *m = a->priv;
155 struct net_device *dev;
156 struct sk_buff *skb2;
160 spin_lock(&m->tcf_lock);
161 m->tcf_tm.lastuse = jiffies;
162 bstats_update(&m->tcf_bstats, skb);
166 printk_once(KERN_NOTICE "tc mirred: target device is gone\n");
170 if (!(dev->flags & IFF_UP)) {
171 net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
176 at = G_TC_AT(skb->tc_verd);
177 skb2 = skb_act_clone(skb, GFP_ATOMIC, m->tcf_action);
181 if (!(at & AT_EGRESS)) {
183 skb_push(skb2, skb2->dev->hard_header_len);
186 /* mirror is always swallowed */
187 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
188 skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
190 skb2->skb_iif = skb->dev->ifindex;
192 err = dev_queue_xmit(skb2);
196 m->tcf_qstats.overlimits++;
197 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
198 retval = TC_ACT_SHOT;
200 retval = m->tcf_action;
202 retval = m->tcf_action;
203 spin_unlock(&m->tcf_lock);
208 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
210 unsigned char *b = skb_tail_pointer(skb);
211 struct tcf_mirred *m = a->priv;
212 struct tc_mirred opt = {
213 .index = m->tcf_index,
214 .action = m->tcf_action,
215 .refcnt = m->tcf_refcnt - ref,
216 .bindcnt = m->tcf_bindcnt - bind,
217 .eaction = m->tcfm_eaction,
218 .ifindex = m->tcfm_ifindex,
222 if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
223 goto nla_put_failure;
224 t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
225 t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
226 t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
227 if (nla_put(skb, TCA_MIRRED_TM, sizeof(t), &t))
228 goto nla_put_failure;
236 static int mirred_device_event(struct notifier_block *unused,
237 unsigned long event, void *ptr)
239 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
240 struct tcf_mirred *m;
242 if (event == NETDEV_UNREGISTER)
243 list_for_each_entry(m, &mirred_list, tcfm_list) {
244 if (m->tcfm_dev == dev) {
253 static struct notifier_block mirred_device_notifier = {
254 .notifier_call = mirred_device_event,
257 static struct tc_action_ops act_mirred_ops = {
259 .hinfo = &mirred_hash_info,
260 .type = TCA_ACT_MIRRED,
261 .capab = TCA_CAP_NONE,
262 .owner = THIS_MODULE,
264 .dump = tcf_mirred_dump,
265 .cleanup = tcf_mirred_cleanup,
266 .init = tcf_mirred_init,
269 MODULE_AUTHOR("Jamal Hadi Salim(2002)");
270 MODULE_DESCRIPTION("Device Mirror/redirect actions");
271 MODULE_LICENSE("GPL");
273 static int __init mirred_init_module(void)
275 int err = register_netdevice_notifier(&mirred_device_notifier);
279 err = tcf_hashinfo_init(&mirred_hash_info, MIRRED_TAB_MASK);
281 unregister_netdevice_notifier(&mirred_device_notifier);
284 pr_info("Mirror/redirect action on\n");
285 return tcf_register_action(&act_mirred_ops);
288 static void __exit mirred_cleanup_module(void)
290 tcf_unregister_action(&act_mirred_ops);
291 tcf_hashinfo_destroy(&mirred_hash_info);
292 unregister_netdevice_notifier(&mirred_device_notifier);
295 module_init(mirred_init_module);
296 module_exit(mirred_cleanup_module);