Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
0c6965dd | 2 | * net/sched/act_mirred.c packet mirroring and redirect actions |
1da177e4 LT |
3 | * |
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. | |
8 | * | |
9 | * Authors: Jamal Hadi Salim (2002-4) | |
10 | * | |
11 | * TODO: Add ingress support (and socket redirect support) | |
12 | * | |
13 | */ | |
14 | ||
1da177e4 LT |
15 | #include <linux/types.h> |
16 | #include <linux/kernel.h> | |
1da177e4 | 17 | #include <linux/string.h> |
1da177e4 | 18 | #include <linux/errno.h> |
1da177e4 LT |
19 | #include <linux/skbuff.h> |
20 | #include <linux/rtnetlink.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/init.h> | |
5a0e3ad6 | 23 | #include <linux/gfp.h> |
881d966b | 24 | #include <net/net_namespace.h> |
dc5fc579 | 25 | #include <net/netlink.h> |
1da177e4 LT |
26 | #include <net/pkt_sched.h> |
27 | #include <linux/tc_act/tc_mirred.h> | |
28 | #include <net/tc_act/tc_mirred.h> | |
29 | ||
1da177e4 LT |
30 | #include <linux/if_arp.h> |
31 | ||
e9ce1cd3 | 32 | #define MIRRED_TAB_MASK 7 |
3b87956e | 33 | static LIST_HEAD(mirred_list); |
6bd00b85 | 34 | static DEFINE_SPINLOCK(mirred_list_lock); |
1da177e4 | 35 | |
a5b5c958 | 36 | static void tcf_mirred_release(struct tc_action *a, int bind) |
1da177e4 | 37 | { |
86062033 | 38 | struct tcf_mirred *m = to_mirred(a); |
2ee22a90 ED |
39 | struct net_device *dev = rcu_dereference_protected(m->tcfm_dev, 1); |
40 | ||
6bd00b85 WC |
41 | /* We could be called either in a RCU callback or with RTNL lock held. */ |
42 | spin_lock_bh(&mirred_list_lock); | |
a5b5c958 | 43 | list_del(&m->tcfm_list); |
6bd00b85 | 44 | spin_unlock_bh(&mirred_list_lock); |
2ee22a90 ED |
45 | if (dev) |
46 | dev_put(dev); | |
1da177e4 LT |
47 | } |
48 | ||
53b2bf3f PM |
49 | static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { |
50 | [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, | |
51 | }; | |
52 | ||
ddf97ccd WC |
53 | static int mirred_net_id; |
54 | ||
c1b52739 BL |
55 | static int tcf_mirred_init(struct net *net, struct nlattr *nla, |
56 | struct nlattr *est, struct tc_action *a, int ovr, | |
57 | int bind) | |
1da177e4 | 58 | { |
ddf97ccd | 59 | struct tc_action_net *tn = net_generic(net, mirred_net_id); |
7ba699c6 | 60 | struct nlattr *tb[TCA_MIRRED_MAX + 1]; |
1da177e4 | 61 | struct tc_mirred *parm; |
e9ce1cd3 | 62 | struct tcf_mirred *m; |
b76965e0 | 63 | struct net_device *dev; |
87dfbdc6 | 64 | int ret, ok_push = 0, exists = 0; |
1da177e4 | 65 | |
cee63723 | 66 | if (nla == NULL) |
1da177e4 | 67 | return -EINVAL; |
b76965e0 CG |
68 | ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy); |
69 | if (ret < 0) | |
70 | return ret; | |
53b2bf3f | 71 | if (tb[TCA_MIRRED_PARMS] == NULL) |
1da177e4 | 72 | return -EINVAL; |
7ba699c6 | 73 | parm = nla_data(tb[TCA_MIRRED_PARMS]); |
87dfbdc6 JHS |
74 | |
75 | exists = tcf_hash_check(tn, parm->index, a, bind); | |
76 | if (exists && bind) | |
77 | return 0; | |
78 | ||
b76965e0 CG |
79 | switch (parm->eaction) { |
80 | case TCA_EGRESS_MIRROR: | |
81 | case TCA_EGRESS_REDIR: | |
82 | break; | |
83 | default: | |
87dfbdc6 JHS |
84 | if (exists) |
85 | tcf_hash_release(a, bind); | |
b76965e0 CG |
86 | return -EINVAL; |
87 | } | |
1da177e4 | 88 | if (parm->ifindex) { |
c1b52739 | 89 | dev = __dev_get_by_index(net, parm->ifindex); |
87dfbdc6 JHS |
90 | if (dev == NULL) { |
91 | if (exists) | |
92 | tcf_hash_release(a, bind); | |
1da177e4 | 93 | return -ENODEV; |
87dfbdc6 | 94 | } |
1da177e4 | 95 | switch (dev->type) { |
b76965e0 CG |
96 | case ARPHRD_TUNNEL: |
97 | case ARPHRD_TUNNEL6: | |
98 | case ARPHRD_SIT: | |
99 | case ARPHRD_IPGRE: | |
100 | case ARPHRD_VOID: | |
101 | case ARPHRD_NONE: | |
102 | ok_push = 0; | |
103 | break; | |
104 | default: | |
105 | ok_push = 1; | |
106 | break; | |
1da177e4 | 107 | } |
b76965e0 CG |
108 | } else { |
109 | dev = NULL; | |
1da177e4 LT |
110 | } |
111 | ||
87dfbdc6 | 112 | if (!exists) { |
b76965e0 | 113 | if (dev == NULL) |
1da177e4 | 114 | return -EINVAL; |
ddf97ccd WC |
115 | ret = tcf_hash_create(tn, parm->index, est, a, |
116 | sizeof(*m), bind, true); | |
86062033 WC |
117 | if (ret) |
118 | return ret; | |
1da177e4 LT |
119 | ret = ACT_P_CREATED; |
120 | } else { | |
215c90af WC |
121 | tcf_hash_release(a, bind); |
122 | if (!ovr) | |
1da177e4 | 123 | return -EEXIST; |
1da177e4 | 124 | } |
86062033 | 125 | m = to_mirred(a); |
1da177e4 | 126 | |
2ee22a90 | 127 | ASSERT_RTNL(); |
e9ce1cd3 DM |
128 | m->tcf_action = parm->action; |
129 | m->tcfm_eaction = parm->eaction; | |
b76965e0 | 130 | if (dev != NULL) { |
e9ce1cd3 | 131 | m->tcfm_ifindex = parm->ifindex; |
1da177e4 | 132 | if (ret != ACT_P_CREATED) |
2ee22a90 | 133 | dev_put(rcu_dereference_protected(m->tcfm_dev, 1)); |
1da177e4 | 134 | dev_hold(dev); |
2ee22a90 | 135 | rcu_assign_pointer(m->tcfm_dev, dev); |
e9ce1cd3 | 136 | m->tcfm_ok_push = ok_push; |
1da177e4 | 137 | } |
2ee22a90 | 138 | |
3b87956e | 139 | if (ret == ACT_P_CREATED) { |
6bd00b85 | 140 | spin_lock_bh(&mirred_list_lock); |
3b87956e | 141 | list_add(&m->tcfm_list, &mirred_list); |
6bd00b85 | 142 | spin_unlock_bh(&mirred_list_lock); |
ddf97ccd | 143 | tcf_hash_insert(tn, a); |
3b87956e | 144 | } |
1da177e4 | 145 | |
1da177e4 LT |
146 | return ret; |
147 | } | |
148 | ||
dc7f9f6e | 149 | static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, |
e9ce1cd3 | 150 | struct tcf_result *res) |
1da177e4 | 151 | { |
e9ce1cd3 | 152 | struct tcf_mirred *m = a->priv; |
1da177e4 | 153 | struct net_device *dev; |
feed1f17 | 154 | struct sk_buff *skb2; |
2ee22a90 | 155 | int retval, err; |
feed1f17 | 156 | u32 at; |
1da177e4 | 157 | |
2ee22a90 ED |
158 | tcf_lastuse_update(&m->tcf_tm); |
159 | ||
160 | bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb); | |
1da177e4 | 161 | |
2ee22a90 ED |
162 | rcu_read_lock(); |
163 | retval = READ_ONCE(m->tcf_action); | |
164 | dev = rcu_dereference(m->tcfm_dev); | |
165 | if (unlikely(!dev)) { | |
166 | pr_notice_once("tc mirred: target device is gone\n"); | |
3b87956e | 167 | goto out; |
168 | } | |
169 | ||
2ee22a90 | 170 | if (unlikely(!(dev->flags & IFF_UP))) { |
e87cc472 JP |
171 | net_notice_ratelimited("tc mirred to Houston: device %s is down\n", |
172 | dev->name); | |
feed1f17 | 173 | goto out; |
1da177e4 LT |
174 | } |
175 | ||
210d6de7 | 176 | at = G_TC_AT(skb->tc_verd); |
e578d9c0 | 177 | skb2 = skb_clone(skb, GFP_ATOMIC); |
2ee22a90 | 178 | if (!skb2) |
feed1f17 | 179 | goto out; |
1da177e4 | 180 | |
feed1f17 | 181 | if (!(at & AT_EGRESS)) { |
e9ce1cd3 | 182 | if (m->tcfm_ok_push) |
f40ae913 | 183 | skb_push(skb2, skb->mac_len); |
feed1f17 | 184 | } |
1da177e4 LT |
185 | |
186 | /* mirror is always swallowed */ | |
e9ce1cd3 | 187 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) |
1da177e4 LT |
188 | skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); |
189 | ||
8964be4a | 190 | skb2->skb_iif = skb->dev->ifindex; |
210d6de7 | 191 | skb2->dev = dev; |
8919bc13 | 192 | err = dev_queue_xmit(skb2); |
feed1f17 | 193 | |
feed1f17 | 194 | if (err) { |
2ee22a90 ED |
195 | out: |
196 | qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats)); | |
16c0b164 JW |
197 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) |
198 | retval = TC_ACT_SHOT; | |
2ee22a90 ED |
199 | } |
200 | rcu_read_unlock(); | |
feed1f17 CG |
201 | |
202 | return retval; | |
1da177e4 LT |
203 | } |
204 | ||
e9ce1cd3 | 205 | static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) |
1da177e4 | 206 | { |
27a884dc | 207 | unsigned char *b = skb_tail_pointer(skb); |
e9ce1cd3 | 208 | struct tcf_mirred *m = a->priv; |
1c40be12 ED |
209 | struct tc_mirred opt = { |
210 | .index = m->tcf_index, | |
211 | .action = m->tcf_action, | |
212 | .refcnt = m->tcf_refcnt - ref, | |
213 | .bindcnt = m->tcf_bindcnt - bind, | |
214 | .eaction = m->tcfm_eaction, | |
215 | .ifindex = m->tcfm_ifindex, | |
216 | }; | |
1da177e4 LT |
217 | struct tcf_t t; |
218 | ||
1b34ec43 DM |
219 | if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) |
220 | goto nla_put_failure; | |
e9ce1cd3 DM |
221 | t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install); |
222 | t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse); | |
223 | t.expires = jiffies_to_clock_t(m->tcf_tm.expires); | |
9854518e | 224 | if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD)) |
1b34ec43 | 225 | goto nla_put_failure; |
1da177e4 LT |
226 | return skb->len; |
227 | ||
7ba699c6 | 228 | nla_put_failure: |
dc5fc579 | 229 | nlmsg_trim(skb, b); |
1da177e4 LT |
230 | return -1; |
231 | } | |
232 | ||
ddf97ccd WC |
233 | static int tcf_mirred_walker(struct net *net, struct sk_buff *skb, |
234 | struct netlink_callback *cb, int type, | |
235 | struct tc_action *a) | |
236 | { | |
237 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
238 | ||
239 | return tcf_generic_walker(tn, skb, cb, type, a); | |
240 | } | |
241 | ||
242 | static int tcf_mirred_search(struct net *net, struct tc_action *a, u32 index) | |
243 | { | |
244 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
245 | ||
246 | return tcf_hash_search(tn, a, index); | |
247 | } | |
248 | ||
3b87956e | 249 | static int mirred_device_event(struct notifier_block *unused, |
250 | unsigned long event, void *ptr) | |
251 | { | |
351638e7 | 252 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
3b87956e | 253 | struct tcf_mirred *m; |
254 | ||
2ee22a90 | 255 | ASSERT_RTNL(); |
6bd00b85 WC |
256 | if (event == NETDEV_UNREGISTER) { |
257 | spin_lock_bh(&mirred_list_lock); | |
3b87956e | 258 | list_for_each_entry(m, &mirred_list, tcfm_list) { |
2ee22a90 | 259 | if (rcu_access_pointer(m->tcfm_dev) == dev) { |
3b87956e | 260 | dev_put(dev); |
2ee22a90 ED |
261 | /* Note : no rcu grace period necessary, as |
262 | * net_device are already rcu protected. | |
263 | */ | |
264 | RCU_INIT_POINTER(m->tcfm_dev, NULL); | |
3b87956e | 265 | } |
266 | } | |
6bd00b85 WC |
267 | spin_unlock_bh(&mirred_list_lock); |
268 | } | |
3b87956e | 269 | |
270 | return NOTIFY_DONE; | |
271 | } | |
272 | ||
273 | static struct notifier_block mirred_device_notifier = { | |
274 | .notifier_call = mirred_device_event, | |
275 | }; | |
276 | ||
1da177e4 LT |
277 | static struct tc_action_ops act_mirred_ops = { |
278 | .kind = "mirred", | |
279 | .type = TCA_ACT_MIRRED, | |
1da177e4 LT |
280 | .owner = THIS_MODULE, |
281 | .act = tcf_mirred, | |
282 | .dump = tcf_mirred_dump, | |
86062033 | 283 | .cleanup = tcf_mirred_release, |
1da177e4 | 284 | .init = tcf_mirred_init, |
ddf97ccd WC |
285 | .walk = tcf_mirred_walker, |
286 | .lookup = tcf_mirred_search, | |
287 | }; | |
288 | ||
289 | static __net_init int mirred_init_net(struct net *net) | |
290 | { | |
291 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
292 | ||
293 | return tc_action_net_init(tn, &act_mirred_ops, MIRRED_TAB_MASK); | |
294 | } | |
295 | ||
296 | static void __net_exit mirred_exit_net(struct net *net) | |
297 | { | |
298 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
299 | ||
300 | tc_action_net_exit(tn); | |
301 | } | |
302 | ||
303 | static struct pernet_operations mirred_net_ops = { | |
304 | .init = mirred_init_net, | |
305 | .exit = mirred_exit_net, | |
306 | .id = &mirred_net_id, | |
307 | .size = sizeof(struct tc_action_net), | |
1da177e4 LT |
308 | }; |
309 | ||
310 | MODULE_AUTHOR("Jamal Hadi Salim(2002)"); | |
311 | MODULE_DESCRIPTION("Device Mirror/redirect actions"); | |
312 | MODULE_LICENSE("GPL"); | |
313 | ||
e9ce1cd3 | 314 | static int __init mirred_init_module(void) |
1da177e4 | 315 | { |
3b87956e | 316 | int err = register_netdevice_notifier(&mirred_device_notifier); |
317 | if (err) | |
318 | return err; | |
319 | ||
6ff9c364 | 320 | pr_info("Mirror/redirect action on\n"); |
ddf97ccd | 321 | return tcf_register_action(&act_mirred_ops, &mirred_net_ops); |
1da177e4 LT |
322 | } |
323 | ||
e9ce1cd3 | 324 | static void __exit mirred_cleanup_module(void) |
1da177e4 | 325 | { |
ddf97ccd | 326 | tcf_unregister_action(&act_mirred_ops, &mirred_net_ops); |
568a153a | 327 | unregister_netdevice_notifier(&mirred_device_notifier); |
1da177e4 LT |
328 | } |
329 | ||
330 | module_init(mirred_init_module); | |
331 | module_exit(mirred_cleanup_module); |