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Commit | Line | Data |
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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> |
c491680f | 24 | #include <linux/if_arp.h> |
881d966b | 25 | #include <net/net_namespace.h> |
dc5fc579 | 26 | #include <net/netlink.h> |
1da177e4 LT |
27 | #include <net/pkt_sched.h> |
28 | #include <linux/tc_act/tc_mirred.h> | |
29 | #include <net/tc_act/tc_mirred.h> | |
30 | ||
e9ce1cd3 | 31 | #define MIRRED_TAB_MASK 7 |
3b87956e | 32 | static LIST_HEAD(mirred_list); |
6bd00b85 | 33 | static DEFINE_SPINLOCK(mirred_list_lock); |
1da177e4 | 34 | |
53592b36 SL |
35 | static bool tcf_mirred_is_act_redirect(int action) |
36 | { | |
37 | return action == TCA_EGRESS_REDIR || action == TCA_INGRESS_REDIR; | |
38 | } | |
39 | ||
8dc07fdb | 40 | static bool tcf_mirred_act_wants_ingress(int action) |
53592b36 SL |
41 | { |
42 | switch (action) { | |
43 | case TCA_EGRESS_REDIR: | |
44 | case TCA_EGRESS_MIRROR: | |
8dc07fdb | 45 | return false; |
53592b36 SL |
46 | case TCA_INGRESS_REDIR: |
47 | case TCA_INGRESS_MIRROR: | |
8dc07fdb | 48 | return true; |
53592b36 SL |
49 | default: |
50 | BUG(); | |
51 | } | |
52 | } | |
53 | ||
a5b5c958 | 54 | static void tcf_mirred_release(struct tc_action *a, int bind) |
1da177e4 | 55 | { |
86062033 | 56 | struct tcf_mirred *m = to_mirred(a); |
dc327f89 | 57 | struct net_device *dev; |
2ee22a90 | 58 | |
6bd00b85 WC |
59 | /* We could be called either in a RCU callback or with RTNL lock held. */ |
60 | spin_lock_bh(&mirred_list_lock); | |
a5b5c958 | 61 | list_del(&m->tcfm_list); |
dc327f89 | 62 | dev = rcu_dereference_protected(m->tcfm_dev, 1); |
2ee22a90 ED |
63 | if (dev) |
64 | dev_put(dev); | |
dc327f89 | 65 | spin_unlock_bh(&mirred_list_lock); |
1da177e4 LT |
66 | } |
67 | ||
53b2bf3f PM |
68 | static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { |
69 | [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, | |
70 | }; | |
71 | ||
c7d03a00 | 72 | static unsigned int mirred_net_id; |
a85a970a | 73 | static struct tc_action_ops act_mirred_ops; |
ddf97ccd | 74 | |
c1b52739 | 75 | static int tcf_mirred_init(struct net *net, struct nlattr *nla, |
a85a970a | 76 | struct nlattr *est, struct tc_action **a, int ovr, |
c1b52739 | 77 | int bind) |
1da177e4 | 78 | { |
ddf97ccd | 79 | struct tc_action_net *tn = net_generic(net, mirred_net_id); |
7ba699c6 | 80 | struct nlattr *tb[TCA_MIRRED_MAX + 1]; |
16577923 | 81 | bool mac_header_xmit = false; |
1da177e4 | 82 | struct tc_mirred *parm; |
e9ce1cd3 | 83 | struct tcf_mirred *m; |
b76965e0 | 84 | struct net_device *dev; |
b2313077 | 85 | bool exists = false; |
16577923 | 86 | int ret; |
1da177e4 | 87 | |
cee63723 | 88 | if (nla == NULL) |
1da177e4 | 89 | return -EINVAL; |
fceb6435 | 90 | ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL); |
b76965e0 CG |
91 | if (ret < 0) |
92 | return ret; | |
53b2bf3f | 93 | if (tb[TCA_MIRRED_PARMS] == NULL) |
1da177e4 | 94 | return -EINVAL; |
7ba699c6 | 95 | parm = nla_data(tb[TCA_MIRRED_PARMS]); |
87dfbdc6 JHS |
96 | |
97 | exists = tcf_hash_check(tn, parm->index, a, bind); | |
98 | if (exists && bind) | |
99 | return 0; | |
100 | ||
b76965e0 CG |
101 | switch (parm->eaction) { |
102 | case TCA_EGRESS_MIRROR: | |
103 | case TCA_EGRESS_REDIR: | |
53592b36 SL |
104 | case TCA_INGRESS_REDIR: |
105 | case TCA_INGRESS_MIRROR: | |
b76965e0 CG |
106 | break; |
107 | default: | |
87dfbdc6 | 108 | if (exists) |
a85a970a | 109 | tcf_hash_release(*a, bind); |
b76965e0 CG |
110 | return -EINVAL; |
111 | } | |
1da177e4 | 112 | if (parm->ifindex) { |
c1b52739 | 113 | dev = __dev_get_by_index(net, parm->ifindex); |
87dfbdc6 JHS |
114 | if (dev == NULL) { |
115 | if (exists) | |
a85a970a | 116 | tcf_hash_release(*a, bind); |
1da177e4 | 117 | return -ENODEV; |
87dfbdc6 | 118 | } |
dcf80034 | 119 | mac_header_xmit = dev_is_mac_header_xmit(dev); |
b76965e0 CG |
120 | } else { |
121 | dev = NULL; | |
1da177e4 LT |
122 | } |
123 | ||
87dfbdc6 | 124 | if (!exists) { |
b76965e0 | 125 | if (dev == NULL) |
1da177e4 | 126 | return -EINVAL; |
ddf97ccd | 127 | ret = tcf_hash_create(tn, parm->index, est, a, |
a85a970a | 128 | &act_mirred_ops, bind, true); |
86062033 WC |
129 | if (ret) |
130 | return ret; | |
1da177e4 LT |
131 | ret = ACT_P_CREATED; |
132 | } else { | |
a85a970a | 133 | tcf_hash_release(*a, bind); |
215c90af | 134 | if (!ovr) |
1da177e4 | 135 | return -EEXIST; |
1da177e4 | 136 | } |
a85a970a | 137 | m = to_mirred(*a); |
1da177e4 | 138 | |
2ee22a90 | 139 | ASSERT_RTNL(); |
e9ce1cd3 DM |
140 | m->tcf_action = parm->action; |
141 | m->tcfm_eaction = parm->eaction; | |
b76965e0 | 142 | if (dev != NULL) { |
e9ce1cd3 | 143 | m->tcfm_ifindex = parm->ifindex; |
1da177e4 | 144 | if (ret != ACT_P_CREATED) |
2ee22a90 | 145 | dev_put(rcu_dereference_protected(m->tcfm_dev, 1)); |
1da177e4 | 146 | dev_hold(dev); |
2ee22a90 | 147 | rcu_assign_pointer(m->tcfm_dev, dev); |
16577923 | 148 | m->tcfm_mac_header_xmit = mac_header_xmit; |
1da177e4 | 149 | } |
2ee22a90 | 150 | |
3b87956e | 151 | if (ret == ACT_P_CREATED) { |
6bd00b85 | 152 | spin_lock_bh(&mirred_list_lock); |
3b87956e | 153 | list_add(&m->tcfm_list, &mirred_list); |
6bd00b85 | 154 | spin_unlock_bh(&mirred_list_lock); |
a85a970a | 155 | tcf_hash_insert(tn, *a); |
3b87956e | 156 | } |
1da177e4 | 157 | |
1da177e4 LT |
158 | return ret; |
159 | } | |
160 | ||
dc7f9f6e | 161 | static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, |
e9ce1cd3 | 162 | struct tcf_result *res) |
1da177e4 | 163 | { |
a85a970a | 164 | struct tcf_mirred *m = to_mirred(a); |
53592b36 | 165 | bool m_mac_header_xmit; |
1da177e4 | 166 | struct net_device *dev; |
feed1f17 | 167 | struct sk_buff *skb2; |
53592b36 SL |
168 | int retval, err = 0; |
169 | int m_eaction; | |
170 | int mac_len; | |
1da177e4 | 171 | |
2ee22a90 | 172 | tcf_lastuse_update(&m->tcf_tm); |
2ee22a90 | 173 | bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb); |
1da177e4 | 174 | |
2ee22a90 | 175 | rcu_read_lock(); |
53592b36 SL |
176 | m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit); |
177 | m_eaction = READ_ONCE(m->tcfm_eaction); | |
2ee22a90 ED |
178 | retval = READ_ONCE(m->tcf_action); |
179 | dev = rcu_dereference(m->tcfm_dev); | |
180 | if (unlikely(!dev)) { | |
181 | pr_notice_once("tc mirred: target device is gone\n"); | |
3b87956e | 182 | goto out; |
183 | } | |
184 | ||
2ee22a90 | 185 | if (unlikely(!(dev->flags & IFF_UP))) { |
e87cc472 JP |
186 | net_notice_ratelimited("tc mirred to Houston: device %s is down\n", |
187 | dev->name); | |
feed1f17 | 188 | goto out; |
1da177e4 LT |
189 | } |
190 | ||
e578d9c0 | 191 | skb2 = skb_clone(skb, GFP_ATOMIC); |
2ee22a90 | 192 | if (!skb2) |
feed1f17 | 193 | goto out; |
1da177e4 | 194 | |
53592b36 SL |
195 | /* If action's target direction differs than filter's direction, |
196 | * and devices expect a mac header on xmit, then mac push/pull is | |
197 | * needed. | |
198 | */ | |
8dc07fdb | 199 | if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) && |
a5135bcf WB |
200 | m_mac_header_xmit) { |
201 | if (!skb_at_tc_ingress(skb)) { | |
53592b36 SL |
202 | /* caught at egress, act ingress: pull mac */ |
203 | mac_len = skb_network_header(skb) - skb_mac_header(skb); | |
204 | skb_pull_rcsum(skb2, mac_len); | |
205 | } else { | |
206 | /* caught at ingress, act egress: push mac */ | |
82a31b92 | 207 | skb_push_rcsum(skb2, skb->mac_len); |
53592b36 | 208 | } |
feed1f17 | 209 | } |
1da177e4 LT |
210 | |
211 | /* mirror is always swallowed */ | |
bc31c905 WB |
212 | if (tcf_mirred_is_act_redirect(m_eaction)) { |
213 | skb2->tc_redirected = 1; | |
214 | skb2->tc_from_ingress = skb2->tc_at_ingress; | |
215 | } | |
1da177e4 | 216 | |
8964be4a | 217 | skb2->skb_iif = skb->dev->ifindex; |
210d6de7 | 218 | skb2->dev = dev; |
8dc07fdb | 219 | if (!tcf_mirred_act_wants_ingress(m_eaction)) |
53592b36 SL |
220 | err = dev_queue_xmit(skb2); |
221 | else | |
222 | err = netif_receive_skb(skb2); | |
feed1f17 | 223 | |
feed1f17 | 224 | if (err) { |
2ee22a90 ED |
225 | out: |
226 | qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats)); | |
53592b36 | 227 | if (tcf_mirred_is_act_redirect(m_eaction)) |
16c0b164 | 228 | retval = TC_ACT_SHOT; |
2ee22a90 ED |
229 | } |
230 | rcu_read_unlock(); | |
feed1f17 CG |
231 | |
232 | return retval; | |
1da177e4 LT |
233 | } |
234 | ||
9798e6fe JK |
235 | static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets, |
236 | u64 lastuse) | |
237 | { | |
5712bf9c PB |
238 | struct tcf_mirred *m = to_mirred(a); |
239 | struct tcf_t *tm = &m->tcf_tm; | |
240 | ||
9798e6fe | 241 | _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets); |
5712bf9c | 242 | tm->lastuse = lastuse; |
9798e6fe JK |
243 | } |
244 | ||
5a7a5555 JHS |
245 | static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, |
246 | int ref) | |
1da177e4 | 247 | { |
27a884dc | 248 | unsigned char *b = skb_tail_pointer(skb); |
a85a970a | 249 | struct tcf_mirred *m = to_mirred(a); |
1c40be12 ED |
250 | struct tc_mirred opt = { |
251 | .index = m->tcf_index, | |
252 | .action = m->tcf_action, | |
253 | .refcnt = m->tcf_refcnt - ref, | |
254 | .bindcnt = m->tcf_bindcnt - bind, | |
255 | .eaction = m->tcfm_eaction, | |
256 | .ifindex = m->tcfm_ifindex, | |
257 | }; | |
1da177e4 LT |
258 | struct tcf_t t; |
259 | ||
1b34ec43 DM |
260 | if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) |
261 | goto nla_put_failure; | |
48d8ee16 JHS |
262 | |
263 | tcf_tm_dump(&t, &m->tcf_tm); | |
9854518e | 264 | if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD)) |
1b34ec43 | 265 | goto nla_put_failure; |
1da177e4 LT |
266 | return skb->len; |
267 | ||
7ba699c6 | 268 | nla_put_failure: |
dc5fc579 | 269 | nlmsg_trim(skb, b); |
1da177e4 LT |
270 | return -1; |
271 | } | |
272 | ||
ddf97ccd WC |
273 | static int tcf_mirred_walker(struct net *net, struct sk_buff *skb, |
274 | struct netlink_callback *cb, int type, | |
a85a970a | 275 | const struct tc_action_ops *ops) |
ddf97ccd WC |
276 | { |
277 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
278 | ||
a85a970a | 279 | return tcf_generic_walker(tn, skb, cb, type, ops); |
ddf97ccd WC |
280 | } |
281 | ||
a85a970a | 282 | static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index) |
ddf97ccd WC |
283 | { |
284 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
285 | ||
286 | return tcf_hash_search(tn, a, index); | |
287 | } | |
288 | ||
3b87956e | 289 | static int mirred_device_event(struct notifier_block *unused, |
290 | unsigned long event, void *ptr) | |
291 | { | |
351638e7 | 292 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
3b87956e | 293 | struct tcf_mirred *m; |
294 | ||
2ee22a90 | 295 | ASSERT_RTNL(); |
6bd00b85 WC |
296 | if (event == NETDEV_UNREGISTER) { |
297 | spin_lock_bh(&mirred_list_lock); | |
3b87956e | 298 | list_for_each_entry(m, &mirred_list, tcfm_list) { |
2ee22a90 | 299 | if (rcu_access_pointer(m->tcfm_dev) == dev) { |
3b87956e | 300 | dev_put(dev); |
2ee22a90 ED |
301 | /* Note : no rcu grace period necessary, as |
302 | * net_device are already rcu protected. | |
303 | */ | |
304 | RCU_INIT_POINTER(m->tcfm_dev, NULL); | |
3b87956e | 305 | } |
306 | } | |
6bd00b85 WC |
307 | spin_unlock_bh(&mirred_list_lock); |
308 | } | |
3b87956e | 309 | |
310 | return NOTIFY_DONE; | |
311 | } | |
312 | ||
313 | static struct notifier_block mirred_device_notifier = { | |
314 | .notifier_call = mirred_device_event, | |
315 | }; | |
316 | ||
255cb304 HHZ |
317 | static int tcf_mirred_device(const struct tc_action *a, struct net *net, |
318 | struct net_device **mirred_dev) | |
319 | { | |
320 | int ifindex = tcf_mirred_ifindex(a); | |
321 | ||
322 | *mirred_dev = __dev_get_by_index(net, ifindex); | |
548ed722 | 323 | if (!*mirred_dev) |
255cb304 HHZ |
324 | return -EINVAL; |
325 | return 0; | |
326 | } | |
327 | ||
1da177e4 LT |
328 | static struct tc_action_ops act_mirred_ops = { |
329 | .kind = "mirred", | |
330 | .type = TCA_ACT_MIRRED, | |
1da177e4 LT |
331 | .owner = THIS_MODULE, |
332 | .act = tcf_mirred, | |
9798e6fe | 333 | .stats_update = tcf_stats_update, |
1da177e4 | 334 | .dump = tcf_mirred_dump, |
86062033 | 335 | .cleanup = tcf_mirred_release, |
1da177e4 | 336 | .init = tcf_mirred_init, |
ddf97ccd WC |
337 | .walk = tcf_mirred_walker, |
338 | .lookup = tcf_mirred_search, | |
a85a970a | 339 | .size = sizeof(struct tcf_mirred), |
255cb304 | 340 | .get_dev = tcf_mirred_device, |
ddf97ccd WC |
341 | }; |
342 | ||
343 | static __net_init int mirred_init_net(struct net *net) | |
344 | { | |
345 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
346 | ||
347 | return tc_action_net_init(tn, &act_mirred_ops, MIRRED_TAB_MASK); | |
348 | } | |
349 | ||
350 | static void __net_exit mirred_exit_net(struct net *net) | |
351 | { | |
352 | struct tc_action_net *tn = net_generic(net, mirred_net_id); | |
353 | ||
354 | tc_action_net_exit(tn); | |
355 | } | |
356 | ||
357 | static struct pernet_operations mirred_net_ops = { | |
358 | .init = mirred_init_net, | |
359 | .exit = mirred_exit_net, | |
360 | .id = &mirred_net_id, | |
361 | .size = sizeof(struct tc_action_net), | |
1da177e4 LT |
362 | }; |
363 | ||
364 | MODULE_AUTHOR("Jamal Hadi Salim(2002)"); | |
365 | MODULE_DESCRIPTION("Device Mirror/redirect actions"); | |
366 | MODULE_LICENSE("GPL"); | |
367 | ||
e9ce1cd3 | 368 | static int __init mirred_init_module(void) |
1da177e4 | 369 | { |
3b87956e | 370 | int err = register_netdevice_notifier(&mirred_device_notifier); |
371 | if (err) | |
372 | return err; | |
373 | ||
6ff9c364 | 374 | pr_info("Mirror/redirect action on\n"); |
ddf97ccd | 375 | return tcf_register_action(&act_mirred_ops, &mirred_net_ops); |
1da177e4 LT |
376 | } |
377 | ||
e9ce1cd3 | 378 | static void __exit mirred_cleanup_module(void) |
1da177e4 | 379 | { |
ddf97ccd | 380 | tcf_unregister_action(&act_mirred_ops, &mirred_net_ops); |
568a153a | 381 | unregister_netdevice_notifier(&mirred_device_notifier); |
1da177e4 LT |
382 | } |
383 | ||
384 | module_init(mirred_init_module); | |
385 | module_exit(mirred_cleanup_module); |