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); |
b9baa0aa | 39 | struct net_device *dev; |
2ee22a90 | 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); |
b9baa0aa | 44 | dev = rcu_dereference_protected(m->tcfm_dev, 1); |
2ee22a90 ED |
45 | if (dev) |
46 | dev_put(dev); | |
b9baa0aa | 47 | spin_unlock_bh(&mirred_list_lock); |
1da177e4 LT |
48 | } |
49 | ||
53b2bf3f PM |
50 | static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { |
51 | [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, | |
52 | }; | |
53 | ||
c1b52739 BL |
54 | static int tcf_mirred_init(struct net *net, struct nlattr *nla, |
55 | struct nlattr *est, struct tc_action *a, int ovr, | |
56 | int bind) | |
1da177e4 | 57 | { |
7ba699c6 | 58 | struct nlattr *tb[TCA_MIRRED_MAX + 1]; |
1da177e4 | 59 | struct tc_mirred *parm; |
e9ce1cd3 | 60 | struct tcf_mirred *m; |
b76965e0 CG |
61 | struct net_device *dev; |
62 | int ret, ok_push = 0; | |
1da177e4 | 63 | |
cee63723 | 64 | if (nla == NULL) |
1da177e4 | 65 | return -EINVAL; |
b76965e0 CG |
66 | ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy); |
67 | if (ret < 0) | |
68 | return ret; | |
53b2bf3f | 69 | if (tb[TCA_MIRRED_PARMS] == NULL) |
1da177e4 | 70 | return -EINVAL; |
7ba699c6 | 71 | parm = nla_data(tb[TCA_MIRRED_PARMS]); |
b76965e0 CG |
72 | switch (parm->eaction) { |
73 | case TCA_EGRESS_MIRROR: | |
74 | case TCA_EGRESS_REDIR: | |
1cac41cb | 75 | case TCA_INGRESS_REDIR: |
b76965e0 CG |
76 | break; |
77 | default: | |
78 | return -EINVAL; | |
79 | } | |
1da177e4 | 80 | if (parm->ifindex) { |
c1b52739 | 81 | dev = __dev_get_by_index(net, parm->ifindex); |
1da177e4 LT |
82 | if (dev == NULL) |
83 | return -ENODEV; | |
84 | switch (dev->type) { | |
b76965e0 CG |
85 | case ARPHRD_TUNNEL: |
86 | case ARPHRD_TUNNEL6: | |
87 | case ARPHRD_SIT: | |
88 | case ARPHRD_IPGRE: | |
89 | case ARPHRD_VOID: | |
90 | case ARPHRD_NONE: | |
91 | ok_push = 0; | |
92 | break; | |
93 | default: | |
94 | ok_push = 1; | |
95 | break; | |
1da177e4 | 96 | } |
b76965e0 CG |
97 | } else { |
98 | dev = NULL; | |
1da177e4 LT |
99 | } |
100 | ||
86062033 | 101 | if (!tcf_hash_check(parm->index, a, bind)) { |
b76965e0 | 102 | if (dev == NULL) |
1da177e4 | 103 | return -EINVAL; |
519c818e | 104 | ret = tcf_hash_create(parm->index, est, a, sizeof(*m), |
2ee22a90 | 105 | bind, true); |
86062033 WC |
106 | if (ret) |
107 | return ret; | |
1da177e4 LT |
108 | ret = ACT_P_CREATED; |
109 | } else { | |
636dba8e WC |
110 | if (bind) |
111 | return 0; | |
215c90af WC |
112 | |
113 | tcf_hash_release(a, bind); | |
114 | if (!ovr) | |
1da177e4 | 115 | return -EEXIST; |
1da177e4 | 116 | } |
86062033 | 117 | m = to_mirred(a); |
1da177e4 | 118 | |
2ee22a90 | 119 | ASSERT_RTNL(); |
e9ce1cd3 DM |
120 | m->tcf_action = parm->action; |
121 | m->tcfm_eaction = parm->eaction; | |
b76965e0 | 122 | if (dev != NULL) { |
e9ce1cd3 | 123 | m->tcfm_ifindex = parm->ifindex; |
1da177e4 | 124 | if (ret != ACT_P_CREATED) |
2ee22a90 | 125 | dev_put(rcu_dereference_protected(m->tcfm_dev, 1)); |
1da177e4 | 126 | dev_hold(dev); |
2ee22a90 | 127 | rcu_assign_pointer(m->tcfm_dev, dev); |
e9ce1cd3 | 128 | m->tcfm_ok_push = ok_push; |
1da177e4 | 129 | } |
2ee22a90 | 130 | |
3b87956e | 131 | if (ret == ACT_P_CREATED) { |
6bd00b85 | 132 | spin_lock_bh(&mirred_list_lock); |
3b87956e | 133 | list_add(&m->tcfm_list, &mirred_list); |
6bd00b85 | 134 | spin_unlock_bh(&mirred_list_lock); |
86062033 | 135 | tcf_hash_insert(a); |
3b87956e | 136 | } |
1da177e4 | 137 | |
1da177e4 LT |
138 | return ret; |
139 | } | |
140 | ||
dc7f9f6e | 141 | static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, |
e9ce1cd3 | 142 | struct tcf_result *res) |
1da177e4 | 143 | { |
e9ce1cd3 | 144 | struct tcf_mirred *m = a->priv; |
1da177e4 | 145 | struct net_device *dev; |
feed1f17 | 146 | struct sk_buff *skb2; |
2ee22a90 | 147 | int retval, err; |
feed1f17 | 148 | u32 at; |
1da177e4 | 149 | |
2ee22a90 ED |
150 | tcf_lastuse_update(&m->tcf_tm); |
151 | ||
152 | bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb); | |
1da177e4 | 153 | |
2ee22a90 ED |
154 | rcu_read_lock(); |
155 | retval = READ_ONCE(m->tcf_action); | |
156 | dev = rcu_dereference(m->tcfm_dev); | |
157 | if (unlikely(!dev)) { | |
158 | pr_notice_once("tc mirred: target device is gone\n"); | |
3b87956e | 159 | goto out; |
160 | } | |
161 | ||
2ee22a90 | 162 | if (unlikely(!(dev->flags & IFF_UP))) { |
e87cc472 JP |
163 | net_notice_ratelimited("tc mirred to Houston: device %s is down\n", |
164 | dev->name); | |
feed1f17 | 165 | goto out; |
1da177e4 LT |
166 | } |
167 | ||
e578d9c0 | 168 | skb2 = skb_clone(skb, GFP_ATOMIC); |
2ee22a90 | 169 | if (!skb2) |
feed1f17 | 170 | goto out; |
1da177e4 | 171 | |
1cac41cb MB |
172 | if (m->tcfm_eaction == TCA_INGRESS_REDIR) { |
173 | /* Let's _hope_ the devices are of similar type. | |
174 | * This is rather dangerous; with changed skb_iif, we | |
175 | * will not know the real input device, but perhaps | |
176 | * that's the whole point of doing the ingress | |
177 | * redirect/mirror in the first place? (Note: This | |
178 | * can lead to bad things if two devices ingress | |
179 | * redirect at each other. Don't do that.)*/ | |
180 | skb2->dev = dev; | |
181 | skb2->skb_iif = skb2->dev->ifindex; | |
182 | skb2->pkt_type = PACKET_HOST; | |
183 | netif_rx(skb2); | |
184 | } else { | |
185 | at = G_TC_AT(skb->tc_verd); | |
186 | if (!(at & AT_EGRESS)) { | |
187 | if (m->tcfm_ok_push) | |
188 | skb_push(skb2, skb->mac_len); | |
189 | } | |
1da177e4 | 190 | |
1cac41cb MB |
191 | /* mirror is always swallowed */ |
192 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) | |
193 | skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); | |
1da177e4 | 194 | |
1cac41cb MB |
195 | skb2->skb_iif = skb->dev->ifindex; |
196 | skb2->dev = dev; | |
197 | skb_sender_cpu_clear(skb2); | |
198 | err = dev_queue_xmit(skb2); | |
199 | } | |
feed1f17 | 200 | |
feed1f17 | 201 | if (err) { |
2ee22a90 ED |
202 | out: |
203 | qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats)); | |
16c0b164 JW |
204 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) |
205 | retval = TC_ACT_SHOT; | |
2ee22a90 ED |
206 | } |
207 | rcu_read_unlock(); | |
feed1f17 CG |
208 | |
209 | return retval; | |
1da177e4 LT |
210 | } |
211 | ||
e9ce1cd3 | 212 | static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) |
1da177e4 | 213 | { |
27a884dc | 214 | unsigned char *b = skb_tail_pointer(skb); |
e9ce1cd3 | 215 | struct tcf_mirred *m = a->priv; |
1c40be12 ED |
216 | struct tc_mirred opt = { |
217 | .index = m->tcf_index, | |
218 | .action = m->tcf_action, | |
219 | .refcnt = m->tcf_refcnt - ref, | |
220 | .bindcnt = m->tcf_bindcnt - bind, | |
221 | .eaction = m->tcfm_eaction, | |
222 | .ifindex = m->tcfm_ifindex, | |
223 | }; | |
1da177e4 LT |
224 | struct tcf_t t; |
225 | ||
1b34ec43 DM |
226 | if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) |
227 | goto nla_put_failure; | |
e9ce1cd3 DM |
228 | t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install); |
229 | t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse); | |
230 | t.expires = jiffies_to_clock_t(m->tcf_tm.expires); | |
1b34ec43 DM |
231 | if (nla_put(skb, TCA_MIRRED_TM, sizeof(t), &t)) |
232 | goto nla_put_failure; | |
1da177e4 LT |
233 | return skb->len; |
234 | ||
7ba699c6 | 235 | nla_put_failure: |
dc5fc579 | 236 | nlmsg_trim(skb, b); |
1da177e4 LT |
237 | return -1; |
238 | } | |
239 | ||
3b87956e | 240 | static int mirred_device_event(struct notifier_block *unused, |
241 | unsigned long event, void *ptr) | |
242 | { | |
351638e7 | 243 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
3b87956e | 244 | struct tcf_mirred *m; |
245 | ||
2ee22a90 | 246 | ASSERT_RTNL(); |
6bd00b85 WC |
247 | if (event == NETDEV_UNREGISTER) { |
248 | spin_lock_bh(&mirred_list_lock); | |
3b87956e | 249 | list_for_each_entry(m, &mirred_list, tcfm_list) { |
2ee22a90 | 250 | if (rcu_access_pointer(m->tcfm_dev) == dev) { |
3b87956e | 251 | dev_put(dev); |
2ee22a90 ED |
252 | /* Note : no rcu grace period necessary, as |
253 | * net_device are already rcu protected. | |
254 | */ | |
255 | RCU_INIT_POINTER(m->tcfm_dev, NULL); | |
3b87956e | 256 | } |
257 | } | |
6bd00b85 WC |
258 | spin_unlock_bh(&mirred_list_lock); |
259 | } | |
3b87956e | 260 | |
261 | return NOTIFY_DONE; | |
262 | } | |
263 | ||
264 | static struct notifier_block mirred_device_notifier = { | |
265 | .notifier_call = mirred_device_event, | |
266 | }; | |
267 | ||
1da177e4 LT |
268 | static struct tc_action_ops act_mirred_ops = { |
269 | .kind = "mirred", | |
270 | .type = TCA_ACT_MIRRED, | |
1da177e4 LT |
271 | .owner = THIS_MODULE, |
272 | .act = tcf_mirred, | |
273 | .dump = tcf_mirred_dump, | |
86062033 | 274 | .cleanup = tcf_mirred_release, |
1da177e4 | 275 | .init = tcf_mirred_init, |
1da177e4 LT |
276 | }; |
277 | ||
278 | MODULE_AUTHOR("Jamal Hadi Salim(2002)"); | |
279 | MODULE_DESCRIPTION("Device Mirror/redirect actions"); | |
280 | MODULE_LICENSE("GPL"); | |
281 | ||
e9ce1cd3 | 282 | static int __init mirred_init_module(void) |
1da177e4 | 283 | { |
3b87956e | 284 | int err = register_netdevice_notifier(&mirred_device_notifier); |
285 | if (err) | |
286 | return err; | |
287 | ||
6ff9c364 | 288 | pr_info("Mirror/redirect action on\n"); |
4f1e9d89 | 289 | return tcf_register_action(&act_mirred_ops, MIRRED_TAB_MASK); |
1da177e4 LT |
290 | } |
291 | ||
e9ce1cd3 | 292 | static void __exit mirred_cleanup_module(void) |
1da177e4 LT |
293 | { |
294 | tcf_unregister_action(&act_mirred_ops); | |
568a153a | 295 | unregister_netdevice_notifier(&mirred_device_notifier); |
1da177e4 LT |
296 | } |
297 | ||
298 | module_init(mirred_init_module); | |
299 | module_exit(mirred_cleanup_module); |