Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * net/sched/mirred.c packet mirroring and redirect actions | |
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 | ||
15 | #include <asm/uaccess.h> | |
16 | #include <asm/system.h> | |
17 | #include <asm/bitops.h> | |
18 | #include <linux/config.h> | |
19 | #include <linux/types.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/sched.h> | |
22 | #include <linux/string.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/socket.h> | |
25 | #include <linux/sockios.h> | |
26 | #include <linux/in.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/interrupt.h> | |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/skbuff.h> | |
31 | #include <linux/rtnetlink.h> | |
32 | #include <linux/module.h> | |
33 | #include <linux/init.h> | |
34 | #include <linux/proc_fs.h> | |
35 | #include <net/sock.h> | |
36 | #include <net/pkt_sched.h> | |
37 | #include <linux/tc_act/tc_mirred.h> | |
38 | #include <net/tc_act/tc_mirred.h> | |
39 | ||
40 | #include <linux/etherdevice.h> | |
41 | #include <linux/if_arp.h> | |
42 | ||
43 | ||
44 | /* use generic hash table */ | |
45 | #define MY_TAB_SIZE 8 | |
46 | #define MY_TAB_MASK (MY_TAB_SIZE - 1) | |
47 | static u32 idx_gen; | |
48 | static struct tcf_mirred *tcf_mirred_ht[MY_TAB_SIZE]; | |
49 | static DEFINE_RWLOCK(mirred_lock); | |
50 | ||
51 | /* ovewrride the defaults */ | |
52 | #define tcf_st tcf_mirred | |
53 | #define tc_st tc_mirred | |
54 | #define tcf_t_lock mirred_lock | |
55 | #define tcf_ht tcf_mirred_ht | |
56 | ||
57 | #define CONFIG_NET_ACT_INIT 1 | |
58 | #include <net/pkt_act.h> | |
59 | ||
60 | static inline int | |
61 | tcf_mirred_release(struct tcf_mirred *p, int bind) | |
62 | { | |
63 | if (p) { | |
64 | if (bind) | |
65 | p->bindcnt--; | |
66 | p->refcnt--; | |
67 | if(!p->bindcnt && p->refcnt <= 0) { | |
68 | dev_put(p->dev); | |
69 | tcf_hash_destroy(p); | |
70 | return 1; | |
71 | } | |
72 | } | |
73 | return 0; | |
74 | } | |
75 | ||
76 | static int | |
77 | tcf_mirred_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a, | |
78 | int ovr, int bind) | |
79 | { | |
80 | struct rtattr *tb[TCA_MIRRED_MAX]; | |
81 | struct tc_mirred *parm; | |
82 | struct tcf_mirred *p; | |
83 | struct net_device *dev = NULL; | |
84 | int ret = 0; | |
85 | int ok_push = 0; | |
86 | ||
87 | if (rta == NULL || rtattr_parse_nested(tb, TCA_MIRRED_MAX, rta) < 0) | |
88 | return -EINVAL; | |
89 | ||
90 | if (tb[TCA_MIRRED_PARMS-1] == NULL || | |
91 | RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm)) | |
92 | return -EINVAL; | |
93 | parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]); | |
94 | ||
95 | if (parm->ifindex) { | |
96 | dev = __dev_get_by_index(parm->ifindex); | |
97 | if (dev == NULL) | |
98 | return -ENODEV; | |
99 | switch (dev->type) { | |
100 | case ARPHRD_TUNNEL: | |
101 | case ARPHRD_TUNNEL6: | |
102 | case ARPHRD_SIT: | |
103 | case ARPHRD_IPGRE: | |
104 | case ARPHRD_VOID: | |
105 | case ARPHRD_NONE: | |
106 | ok_push = 0; | |
107 | break; | |
108 | default: | |
109 | ok_push = 1; | |
110 | break; | |
111 | } | |
112 | } | |
113 | ||
114 | p = tcf_hash_check(parm->index, a, ovr, bind); | |
115 | if (p == NULL) { | |
116 | if (!parm->ifindex) | |
117 | return -EINVAL; | |
118 | p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind); | |
119 | if (p == NULL) | |
120 | return -ENOMEM; | |
121 | ret = ACT_P_CREATED; | |
122 | } else { | |
123 | if (!ovr) { | |
124 | tcf_mirred_release(p, bind); | |
125 | return -EEXIST; | |
126 | } | |
127 | } | |
128 | ||
129 | spin_lock_bh(&p->lock); | |
130 | p->action = parm->action; | |
131 | p->eaction = parm->eaction; | |
132 | if (parm->ifindex) { | |
133 | p->ifindex = parm->ifindex; | |
134 | if (ret != ACT_P_CREATED) | |
135 | dev_put(p->dev); | |
136 | p->dev = dev; | |
137 | dev_hold(dev); | |
138 | p->ok_push = ok_push; | |
139 | } | |
140 | spin_unlock_bh(&p->lock); | |
141 | if (ret == ACT_P_CREATED) | |
142 | tcf_hash_insert(p); | |
143 | ||
144 | DPRINTK("tcf_mirred_init index %d action %d eaction %d device %s " | |
145 | "ifindex %d\n", parm->index, parm->action, parm->eaction, | |
146 | dev->name, parm->ifindex); | |
147 | return ret; | |
148 | } | |
149 | ||
150 | static int | |
151 | tcf_mirred_cleanup(struct tc_action *a, int bind) | |
152 | { | |
153 | struct tcf_mirred *p = PRIV(a, mirred); | |
154 | ||
155 | if (p != NULL) | |
156 | return tcf_mirred_release(p, bind); | |
157 | return 0; | |
158 | } | |
159 | ||
160 | static int | |
161 | tcf_mirred(struct sk_buff **pskb, struct tc_action *a) | |
162 | { | |
163 | struct tcf_mirred *p = PRIV(a, mirred); | |
164 | struct net_device *dev; | |
165 | struct sk_buff *skb2 = NULL; | |
166 | struct sk_buff *skb = *pskb; | |
167 | u32 at = G_TC_AT(skb->tc_verd); | |
168 | ||
169 | spin_lock(&p->lock); | |
170 | ||
171 | dev = p->dev; | |
172 | p->tm.lastuse = jiffies; | |
173 | ||
174 | if (!(dev->flags&IFF_UP) ) { | |
175 | if (net_ratelimit()) | |
176 | printk("mirred to Houston: device %s is gone!\n", | |
177 | dev->name); | |
178 | bad_mirred: | |
179 | if (skb2 != NULL) | |
180 | kfree_skb(skb2); | |
181 | p->qstats.overlimits++; | |
182 | p->bstats.bytes += skb->len; | |
183 | p->bstats.packets++; | |
184 | spin_unlock(&p->lock); | |
185 | /* should we be asking for packet to be dropped? | |
186 | * may make sense for redirect case only | |
187 | */ | |
188 | return TC_ACT_SHOT; | |
189 | } | |
190 | ||
191 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
192 | if (skb2 == NULL) | |
193 | goto bad_mirred; | |
194 | if (p->eaction != TCA_EGRESS_MIRROR && p->eaction != TCA_EGRESS_REDIR) { | |
195 | if (net_ratelimit()) | |
196 | printk("tcf_mirred unknown action %d\n", p->eaction); | |
197 | goto bad_mirred; | |
198 | } | |
199 | ||
200 | p->bstats.bytes += skb2->len; | |
201 | p->bstats.packets++; | |
202 | if (!(at & AT_EGRESS)) | |
203 | if (p->ok_push) | |
204 | skb_push(skb2, skb2->dev->hard_header_len); | |
205 | ||
206 | /* mirror is always swallowed */ | |
207 | if (p->eaction != TCA_EGRESS_MIRROR) | |
208 | skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); | |
209 | ||
210 | skb2->dev = dev; | |
211 | skb2->input_dev = skb->dev; | |
212 | dev_queue_xmit(skb2); | |
213 | spin_unlock(&p->lock); | |
214 | return p->action; | |
215 | } | |
216 | ||
217 | static int | |
218 | tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) | |
219 | { | |
220 | unsigned char *b = skb->tail; | |
221 | struct tc_mirred opt; | |
222 | struct tcf_mirred *p = PRIV(a, mirred); | |
223 | struct tcf_t t; | |
224 | ||
225 | opt.index = p->index; | |
226 | opt.action = p->action; | |
227 | opt.refcnt = p->refcnt - ref; | |
228 | opt.bindcnt = p->bindcnt - bind; | |
229 | opt.eaction = p->eaction; | |
230 | opt.ifindex = p->ifindex; | |
231 | DPRINTK("tcf_mirred_dump index %d action %d eaction %d ifindex %d\n", | |
232 | p->index, p->action, p->eaction, p->ifindex); | |
233 | RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt); | |
234 | t.install = jiffies_to_clock_t(jiffies - p->tm.install); | |
235 | t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse); | |
236 | t.expires = jiffies_to_clock_t(p->tm.expires); | |
237 | RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t); | |
238 | return skb->len; | |
239 | ||
240 | rtattr_failure: | |
241 | skb_trim(skb, b - skb->data); | |
242 | return -1; | |
243 | } | |
244 | ||
245 | static struct tc_action_ops act_mirred_ops = { | |
246 | .kind = "mirred", | |
247 | .type = TCA_ACT_MIRRED, | |
248 | .capab = TCA_CAP_NONE, | |
249 | .owner = THIS_MODULE, | |
250 | .act = tcf_mirred, | |
251 | .dump = tcf_mirred_dump, | |
252 | .cleanup = tcf_mirred_cleanup, | |
253 | .lookup = tcf_hash_search, | |
254 | .init = tcf_mirred_init, | |
255 | .walk = tcf_generic_walker | |
256 | }; | |
257 | ||
258 | MODULE_AUTHOR("Jamal Hadi Salim(2002)"); | |
259 | MODULE_DESCRIPTION("Device Mirror/redirect actions"); | |
260 | MODULE_LICENSE("GPL"); | |
261 | ||
262 | static int __init | |
263 | mirred_init_module(void) | |
264 | { | |
265 | printk("Mirror/redirect action on\n"); | |
266 | return tcf_register_action(&act_mirred_ops); | |
267 | } | |
268 | ||
269 | static void __exit | |
270 | mirred_cleanup_module(void) | |
271 | { | |
272 | tcf_unregister_action(&act_mirred_ops); | |
273 | } | |
274 | ||
275 | module_init(mirred_init_module); | |
276 | module_exit(mirred_cleanup_module); |