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); |
1da177e4 | 34 | |
a5b5c958 | 35 | static void tcf_mirred_release(struct tc_action *a, int bind) |
1da177e4 | 36 | { |
86062033 | 37 | struct tcf_mirred *m = to_mirred(a); |
2ee22a90 ED |
38 | struct net_device *dev = rcu_dereference_protected(m->tcfm_dev, 1); |
39 | ||
a5b5c958 | 40 | list_del(&m->tcfm_list); |
2ee22a90 ED |
41 | if (dev) |
42 | dev_put(dev); | |
1da177e4 LT |
43 | } |
44 | ||
53b2bf3f PM |
45 | static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { |
46 | [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, | |
47 | }; | |
48 | ||
c1b52739 BL |
49 | static int tcf_mirred_init(struct net *net, struct nlattr *nla, |
50 | struct nlattr *est, struct tc_action *a, int ovr, | |
51 | int bind) | |
1da177e4 | 52 | { |
7ba699c6 | 53 | struct nlattr *tb[TCA_MIRRED_MAX + 1]; |
1da177e4 | 54 | struct tc_mirred *parm; |
e9ce1cd3 | 55 | struct tcf_mirred *m; |
b76965e0 CG |
56 | struct net_device *dev; |
57 | int ret, ok_push = 0; | |
1da177e4 | 58 | |
cee63723 | 59 | if (nla == NULL) |
1da177e4 | 60 | return -EINVAL; |
b76965e0 CG |
61 | ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy); |
62 | if (ret < 0) | |
63 | return ret; | |
53b2bf3f | 64 | if (tb[TCA_MIRRED_PARMS] == NULL) |
1da177e4 | 65 | return -EINVAL; |
7ba699c6 | 66 | parm = nla_data(tb[TCA_MIRRED_PARMS]); |
b76965e0 CG |
67 | switch (parm->eaction) { |
68 | case TCA_EGRESS_MIRROR: | |
69 | case TCA_EGRESS_REDIR: | |
70 | break; | |
71 | default: | |
72 | return -EINVAL; | |
73 | } | |
1da177e4 | 74 | if (parm->ifindex) { |
c1b52739 | 75 | dev = __dev_get_by_index(net, parm->ifindex); |
1da177e4 LT |
76 | if (dev == NULL) |
77 | return -ENODEV; | |
78 | switch (dev->type) { | |
b76965e0 CG |
79 | case ARPHRD_TUNNEL: |
80 | case ARPHRD_TUNNEL6: | |
81 | case ARPHRD_SIT: | |
82 | case ARPHRD_IPGRE: | |
83 | case ARPHRD_VOID: | |
84 | case ARPHRD_NONE: | |
85 | ok_push = 0; | |
86 | break; | |
87 | default: | |
88 | ok_push = 1; | |
89 | break; | |
1da177e4 | 90 | } |
b76965e0 CG |
91 | } else { |
92 | dev = NULL; | |
1da177e4 LT |
93 | } |
94 | ||
86062033 | 95 | if (!tcf_hash_check(parm->index, a, bind)) { |
b76965e0 | 96 | if (dev == NULL) |
1da177e4 | 97 | return -EINVAL; |
519c818e | 98 | ret = tcf_hash_create(parm->index, est, a, sizeof(*m), |
2ee22a90 | 99 | bind, true); |
86062033 WC |
100 | if (ret) |
101 | return ret; | |
1da177e4 LT |
102 | ret = ACT_P_CREATED; |
103 | } else { | |
636dba8e WC |
104 | if (bind) |
105 | return 0; | |
1da177e4 | 106 | if (!ovr) { |
a5b5c958 | 107 | tcf_hash_release(a, bind); |
1da177e4 LT |
108 | return -EEXIST; |
109 | } | |
110 | } | |
86062033 | 111 | m = to_mirred(a); |
1da177e4 | 112 | |
2ee22a90 | 113 | ASSERT_RTNL(); |
e9ce1cd3 DM |
114 | m->tcf_action = parm->action; |
115 | m->tcfm_eaction = parm->eaction; | |
b76965e0 | 116 | if (dev != NULL) { |
e9ce1cd3 | 117 | m->tcfm_ifindex = parm->ifindex; |
1da177e4 | 118 | if (ret != ACT_P_CREATED) |
2ee22a90 | 119 | dev_put(rcu_dereference_protected(m->tcfm_dev, 1)); |
1da177e4 | 120 | dev_hold(dev); |
2ee22a90 | 121 | rcu_assign_pointer(m->tcfm_dev, dev); |
e9ce1cd3 | 122 | m->tcfm_ok_push = ok_push; |
1da177e4 | 123 | } |
2ee22a90 | 124 | |
3b87956e | 125 | if (ret == ACT_P_CREATED) { |
126 | list_add(&m->tcfm_list, &mirred_list); | |
86062033 | 127 | tcf_hash_insert(a); |
3b87956e | 128 | } |
1da177e4 | 129 | |
1da177e4 LT |
130 | return ret; |
131 | } | |
132 | ||
dc7f9f6e | 133 | static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, |
e9ce1cd3 | 134 | struct tcf_result *res) |
1da177e4 | 135 | { |
e9ce1cd3 | 136 | struct tcf_mirred *m = a->priv; |
1da177e4 | 137 | struct net_device *dev; |
feed1f17 | 138 | struct sk_buff *skb2; |
2ee22a90 | 139 | int retval, err; |
feed1f17 | 140 | u32 at; |
1da177e4 | 141 | |
2ee22a90 ED |
142 | tcf_lastuse_update(&m->tcf_tm); |
143 | ||
144 | bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb); | |
1da177e4 | 145 | |
2ee22a90 ED |
146 | rcu_read_lock(); |
147 | retval = READ_ONCE(m->tcf_action); | |
148 | dev = rcu_dereference(m->tcfm_dev); | |
149 | if (unlikely(!dev)) { | |
150 | pr_notice_once("tc mirred: target device is gone\n"); | |
3b87956e | 151 | goto out; |
152 | } | |
153 | ||
2ee22a90 | 154 | if (unlikely(!(dev->flags & IFF_UP))) { |
e87cc472 JP |
155 | net_notice_ratelimited("tc mirred to Houston: device %s is down\n", |
156 | dev->name); | |
feed1f17 | 157 | goto out; |
1da177e4 LT |
158 | } |
159 | ||
210d6de7 | 160 | at = G_TC_AT(skb->tc_verd); |
e578d9c0 | 161 | skb2 = skb_clone(skb, GFP_ATOMIC); |
2ee22a90 | 162 | if (!skb2) |
feed1f17 | 163 | goto out; |
1da177e4 | 164 | |
feed1f17 | 165 | if (!(at & AT_EGRESS)) { |
e9ce1cd3 | 166 | if (m->tcfm_ok_push) |
f40ae913 | 167 | skb_push(skb2, skb->mac_len); |
feed1f17 | 168 | } |
1da177e4 LT |
169 | |
170 | /* mirror is always swallowed */ | |
e9ce1cd3 | 171 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) |
1da177e4 LT |
172 | skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); |
173 | ||
8964be4a | 174 | skb2->skb_iif = skb->dev->ifindex; |
210d6de7 | 175 | skb2->dev = dev; |
8919bc13 | 176 | err = dev_queue_xmit(skb2); |
feed1f17 | 177 | |
feed1f17 | 178 | if (err) { |
2ee22a90 ED |
179 | out: |
180 | qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats)); | |
16c0b164 JW |
181 | if (m->tcfm_eaction != TCA_EGRESS_MIRROR) |
182 | retval = TC_ACT_SHOT; | |
2ee22a90 ED |
183 | } |
184 | rcu_read_unlock(); | |
feed1f17 CG |
185 | |
186 | return retval; | |
1da177e4 LT |
187 | } |
188 | ||
e9ce1cd3 | 189 | static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) |
1da177e4 | 190 | { |
27a884dc | 191 | unsigned char *b = skb_tail_pointer(skb); |
e9ce1cd3 | 192 | struct tcf_mirred *m = a->priv; |
1c40be12 ED |
193 | struct tc_mirred opt = { |
194 | .index = m->tcf_index, | |
195 | .action = m->tcf_action, | |
196 | .refcnt = m->tcf_refcnt - ref, | |
197 | .bindcnt = m->tcf_bindcnt - bind, | |
198 | .eaction = m->tcfm_eaction, | |
199 | .ifindex = m->tcfm_ifindex, | |
200 | }; | |
1da177e4 LT |
201 | struct tcf_t t; |
202 | ||
1b34ec43 DM |
203 | if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) |
204 | goto nla_put_failure; | |
e9ce1cd3 DM |
205 | t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install); |
206 | t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse); | |
207 | t.expires = jiffies_to_clock_t(m->tcf_tm.expires); | |
1b34ec43 DM |
208 | if (nla_put(skb, TCA_MIRRED_TM, sizeof(t), &t)) |
209 | goto nla_put_failure; | |
1da177e4 LT |
210 | return skb->len; |
211 | ||
7ba699c6 | 212 | nla_put_failure: |
dc5fc579 | 213 | nlmsg_trim(skb, b); |
1da177e4 LT |
214 | return -1; |
215 | } | |
216 | ||
3b87956e | 217 | static int mirred_device_event(struct notifier_block *unused, |
218 | unsigned long event, void *ptr) | |
219 | { | |
351638e7 | 220 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
3b87956e | 221 | struct tcf_mirred *m; |
222 | ||
2ee22a90 | 223 | ASSERT_RTNL(); |
3b87956e | 224 | if (event == NETDEV_UNREGISTER) |
225 | list_for_each_entry(m, &mirred_list, tcfm_list) { | |
2ee22a90 | 226 | if (rcu_access_pointer(m->tcfm_dev) == dev) { |
3b87956e | 227 | dev_put(dev); |
2ee22a90 ED |
228 | /* Note : no rcu grace period necessary, as |
229 | * net_device are already rcu protected. | |
230 | */ | |
231 | RCU_INIT_POINTER(m->tcfm_dev, NULL); | |
3b87956e | 232 | } |
233 | } | |
234 | ||
235 | return NOTIFY_DONE; | |
236 | } | |
237 | ||
238 | static struct notifier_block mirred_device_notifier = { | |
239 | .notifier_call = mirred_device_event, | |
240 | }; | |
241 | ||
1da177e4 LT |
242 | static struct tc_action_ops act_mirred_ops = { |
243 | .kind = "mirred", | |
244 | .type = TCA_ACT_MIRRED, | |
1da177e4 LT |
245 | .owner = THIS_MODULE, |
246 | .act = tcf_mirred, | |
247 | .dump = tcf_mirred_dump, | |
86062033 | 248 | .cleanup = tcf_mirred_release, |
1da177e4 | 249 | .init = tcf_mirred_init, |
1da177e4 LT |
250 | }; |
251 | ||
252 | MODULE_AUTHOR("Jamal Hadi Salim(2002)"); | |
253 | MODULE_DESCRIPTION("Device Mirror/redirect actions"); | |
254 | MODULE_LICENSE("GPL"); | |
255 | ||
e9ce1cd3 | 256 | static int __init mirred_init_module(void) |
1da177e4 | 257 | { |
3b87956e | 258 | int err = register_netdevice_notifier(&mirred_device_notifier); |
259 | if (err) | |
260 | return err; | |
261 | ||
6ff9c364 | 262 | pr_info("Mirror/redirect action on\n"); |
4f1e9d89 | 263 | return tcf_register_action(&act_mirred_ops, MIRRED_TAB_MASK); |
1da177e4 LT |
264 | } |
265 | ||
e9ce1cd3 | 266 | static void __exit mirred_cleanup_module(void) |
1da177e4 LT |
267 | { |
268 | tcf_unregister_action(&act_mirred_ops); | |
568a153a | 269 | unregister_netdevice_notifier(&mirred_device_notifier); |
1da177e4 LT |
270 | } |
271 | ||
272 | module_init(mirred_init_module); | |
273 | module_exit(mirred_cleanup_module); |