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 <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>
29 #include <linux/if_arp.h>
31 #define MIRRED_TAB_MASK 7
32 static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
33 static u32 mirred_idx_gen;
34 static DEFINE_RWLOCK(mirred_lock);
36 static struct tcf_hashinfo mirred_hash_info = {
37 .htab = tcf_mirred_ht,
38 .hmask = MIRRED_TAB_MASK,
42 static inline int tcf_mirred_release(struct tcf_mirred *m, int bind)
48 if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
50 tcf_hash_destroy(&m->common, &mirred_hash_info);
57 static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
58 [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
61 static int tcf_mirred_init(struct nlattr *nla, struct nlattr *est,
62 struct tc_action *a, int ovr, int bind)
64 struct nlattr *tb[TCA_MIRRED_MAX + 1];
65 struct tc_mirred *parm;
67 struct tcf_common *pc;
68 struct net_device *dev;
73 ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
76 if (tb[TCA_MIRRED_PARMS] == NULL)
78 parm = nla_data(tb[TCA_MIRRED_PARMS]);
79 switch (parm->eaction) {
80 case TCA_EGRESS_MIRROR:
81 case TCA_EGRESS_REDIR:
87 dev = __dev_get_by_index(&init_net, parm->ifindex);
107 pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
111 pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
112 &mirred_idx_gen, &mirred_hash_info);
118 tcf_mirred_release(to_mirred(pc), bind);
124 spin_lock_bh(&m->tcf_lock);
125 m->tcf_action = parm->action;
126 m->tcfm_eaction = parm->eaction;
128 m->tcfm_ifindex = parm->ifindex;
129 if (ret != ACT_P_CREATED)
130 dev_put(m->tcfm_dev);
133 m->tcfm_ok_push = ok_push;
135 spin_unlock_bh(&m->tcf_lock);
136 if (ret == ACT_P_CREATED)
137 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, 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;
164 if (!(dev->flags & IFF_UP)) {
166 printk("mirred to Houston: device %s is gone!\n",
171 skb2 = skb_act_clone(skb, GFP_ATOMIC);
175 m->tcf_bstats.bytes += qdisc_pkt_len(skb2);
176 m->tcf_bstats.packets++;
177 at = G_TC_AT(skb->tc_verd);
178 if (!(at & AT_EGRESS)) {
180 skb_push(skb2, skb2->dev->hard_header_len);
183 /* mirror is always swallowed */
184 if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
185 skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
188 skb2->skb_iif = skb->dev->ifindex;
189 dev_queue_xmit(skb2);
194 m->tcf_qstats.overlimits++;
195 m->tcf_bstats.bytes += qdisc_pkt_len(skb);
196 m->tcf_bstats.packets++;
197 /* should we be asking for packet to be dropped?
198 * may make sense for redirect case only
200 retval = TC_ACT_SHOT;
202 retval = m->tcf_action;
204 spin_unlock(&m->tcf_lock);
209 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
211 unsigned char *b = skb_tail_pointer(skb);
212 struct tcf_mirred *m = a->priv;
213 struct tc_mirred opt;
216 opt.index = m->tcf_index;
217 opt.action = m->tcf_action;
218 opt.refcnt = m->tcf_refcnt - ref;
219 opt.bindcnt = m->tcf_bindcnt - bind;
220 opt.eaction = m->tcfm_eaction;
221 opt.ifindex = m->tcfm_ifindex;
222 NLA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
223 t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
224 t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
225 t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
226 NLA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
234 static struct tc_action_ops act_mirred_ops = {
236 .hinfo = &mirred_hash_info,
237 .type = TCA_ACT_MIRRED,
238 .capab = TCA_CAP_NONE,
239 .owner = THIS_MODULE,
241 .dump = tcf_mirred_dump,
242 .cleanup = tcf_mirred_cleanup,
243 .lookup = tcf_hash_search,
244 .init = tcf_mirred_init,
245 .walk = tcf_generic_walker
248 MODULE_AUTHOR("Jamal Hadi Salim(2002)");
249 MODULE_DESCRIPTION("Device Mirror/redirect actions");
250 MODULE_LICENSE("GPL");
252 static int __init mirred_init_module(void)
254 printk("Mirror/redirect action on\n");
255 return tcf_register_action(&act_mirred_ops);
258 static void __exit mirred_cleanup_module(void)
260 tcf_unregister_action(&act_mirred_ops);
263 module_init(mirred_init_module);
264 module_exit(mirred_cleanup_module);