1 /*
2 * Ioctl handler
3 * Linux ethernet bridge
4 *
5 * Authors:
6 * Lennert Buytenhek <buytenh@gnu.org>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14 #include <linux/capability.h>
15 #include <linux/kernel.h>
16 #include <linux/if_bridge.h>
17 #include <linux/netdevice.h>
18 #include <linux/slab.h>
19 #include <linux/times.h>
20 #include <net/net_namespace.h>
21 #include <asm/uaccess.h>
22 #include "br_private.h"
23
24 /* called with RTNL */
get_bridge_ifindices(struct net * net,int * indices,int num)25 static int get_bridge_ifindices(struct net *net, int *indices, int num)
26 {
27 struct net_device *dev;
28 int i = 0;
29
30 for_each_netdev(net, dev) {
31 if (i >= num)
32 break;
33 if (dev->priv_flags & IFF_EBRIDGE)
34 indices[i++] = dev->ifindex;
35 }
36
37 return i;
38 }
39
40 /* called with RTNL */
get_port_ifindices(struct net_bridge * br,int * ifindices,int num)41 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num)
42 {
43 struct net_bridge_port *p;
44
45 list_for_each_entry(p, &br->port_list, list) {
46 if (p->port_no < num)
47 ifindices[p->port_no] = p->dev->ifindex;
48 }
49 }
50
51 /*
52 * Format up to a page worth of forwarding table entries
53 * userbuf -- where to copy result
54 * maxnum -- maximum number of entries desired
55 * (limited to a page for sanity)
56 * offset -- number of records to skip
57 */
get_fdb_entries(struct net_bridge * br,void __user * userbuf,unsigned long maxnum,unsigned long offset)58 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
59 unsigned long maxnum, unsigned long offset)
60 {
61 int num;
62 void *buf;
63 size_t size;
64
65 /* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */
66 if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry))
67 maxnum = PAGE_SIZE/sizeof(struct __fdb_entry);
68
69 size = maxnum * sizeof(struct __fdb_entry);
70
71 buf = kmalloc(size, GFP_USER);
72 if (!buf)
73 return -ENOMEM;
74
75 num = br_fdb_fillbuf(br, buf, maxnum, offset);
76 if (num > 0) {
77 if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry)))
78 num = -EFAULT;
79 }
80 kfree(buf);
81
82 return num;
83 }
84
85 /* called with RTNL */
add_del_if(struct net_bridge * br,int ifindex,int isadd)86 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
87 {
88 struct net_device *dev;
89 int ret;
90
91 if (!capable(CAP_NET_ADMIN))
92 return -EPERM;
93
94 dev = __dev_get_by_index(dev_net(br->dev), ifindex);
95 if (dev == NULL)
96 return -EINVAL;
97
98 if (isadd)
99 ret = br_add_if(br, dev);
100 else
101 ret = br_del_if(br, dev);
102
103 return ret;
104 }
105
106 /*
107 * Legacy ioctl's through SIOCDEVPRIVATE
108 * This interface is deprecated because it was too difficult to
109 * to do the translation for 32/64bit ioctl compatibility.
110 */
old_dev_ioctl(struct net_device * dev,struct ifreq * rq,int cmd)111 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
112 {
113 struct net_bridge *br = netdev_priv(dev);
114 unsigned long args[4];
115
116 if (copy_from_user(args, rq->ifr_data, sizeof(args)))
117 return -EFAULT;
118
119 switch (args[0]) {
120 case BRCTL_ADD_IF:
121 case BRCTL_DEL_IF:
122 return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
123
124 case BRCTL_GET_BRIDGE_INFO:
125 {
126 struct __bridge_info b;
127
128 memset(&b, 0, sizeof(struct __bridge_info));
129 rcu_read_lock();
130 memcpy(&b.designated_root, &br->designated_root, 8);
131 memcpy(&b.bridge_id, &br->bridge_id, 8);
132 b.root_path_cost = br->root_path_cost;
133 b.max_age = jiffies_to_clock_t(br->max_age);
134 b.hello_time = jiffies_to_clock_t(br->hello_time);
135 b.forward_delay = br->forward_delay;
136 b.bridge_max_age = br->bridge_max_age;
137 b.bridge_hello_time = br->bridge_hello_time;
138 b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
139 b.topology_change = br->topology_change;
140 b.topology_change_detected = br->topology_change_detected;
141 b.root_port = br->root_port;
142
143 b.stp_enabled = (br->stp_enabled != BR_NO_STP);
144 b.ageing_time = jiffies_to_clock_t(br->ageing_time);
145 b.hello_timer_value = br_timer_value(&br->hello_timer);
146 b.tcn_timer_value = br_timer_value(&br->tcn_timer);
147 b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
148 b.gc_timer_value = br_timer_value(&br->gc_timer);
149 rcu_read_unlock();
150
151 if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
152 return -EFAULT;
153
154 return 0;
155 }
156
157 case BRCTL_GET_PORT_LIST:
158 {
159 int num, *indices;
160
161 num = args[2];
162 if (num < 0)
163 return -EINVAL;
164 if (num == 0)
165 num = 256;
166 if (num > BR_MAX_PORTS)
167 num = BR_MAX_PORTS;
168
169 indices = kcalloc(num, sizeof(int), GFP_KERNEL);
170 if (indices == NULL)
171 return -ENOMEM;
172
173 get_port_ifindices(br, indices, num);
174 if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
175 num = -EFAULT;
176 kfree(indices);
177 return num;
178 }
179
180 case BRCTL_SET_BRIDGE_FORWARD_DELAY:
181 if (!capable(CAP_NET_ADMIN))
182 return -EPERM;
183
184 spin_lock_bh(&br->lock);
185 br->bridge_forward_delay = clock_t_to_jiffies(args[1]);
186 if (br_is_root_bridge(br))
187 br->forward_delay = br->bridge_forward_delay;
188 spin_unlock_bh(&br->lock);
189 return 0;
190
191 case BRCTL_SET_BRIDGE_HELLO_TIME:
192 {
193 unsigned long t = clock_t_to_jiffies(args[1]);
194 if (!capable(CAP_NET_ADMIN))
195 return -EPERM;
196
197 if (t < HZ)
198 return -EINVAL;
199
200 spin_lock_bh(&br->lock);
201 br->bridge_hello_time = t;
202 if (br_is_root_bridge(br))
203 br->hello_time = br->bridge_hello_time;
204 spin_unlock_bh(&br->lock);
205 return 0;
206 }
207
208 case BRCTL_SET_BRIDGE_MAX_AGE:
209 if (!capable(CAP_NET_ADMIN))
210 return -EPERM;
211
212 spin_lock_bh(&br->lock);
213 br->bridge_max_age = clock_t_to_jiffies(args[1]);
214 if (br_is_root_bridge(br))
215 br->max_age = br->bridge_max_age;
216 spin_unlock_bh(&br->lock);
217 return 0;
218
219 case BRCTL_SET_AGEING_TIME:
220 if (!capable(CAP_NET_ADMIN))
221 return -EPERM;
222
223 br->ageing_time = clock_t_to_jiffies(args[1]);
224 return 0;
225
226 case BRCTL_GET_PORT_INFO:
227 {
228 struct __port_info p;
229 struct net_bridge_port *pt;
230
231 rcu_read_lock();
232 if ((pt = br_get_port(br, args[2])) == NULL) {
233 rcu_read_unlock();
234 return -EINVAL;
235 }
236
237 memset(&p, 0, sizeof(struct __port_info));
238 memcpy(&p.designated_root, &pt->designated_root, 8);
239 memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
240 p.port_id = pt->port_id;
241 p.designated_port = pt->designated_port;
242 p.path_cost = pt->path_cost;
243 p.designated_cost = pt->designated_cost;
244 p.state = pt->state;
245 p.top_change_ack = pt->topology_change_ack;
246 p.config_pending = pt->config_pending;
247 p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
248 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
249 p.hold_timer_value = br_timer_value(&pt->hold_timer);
250
251 rcu_read_unlock();
252
253 if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
254 return -EFAULT;
255
256 return 0;
257 }
258
259 case BRCTL_SET_BRIDGE_STP_STATE:
260 if (!capable(CAP_NET_ADMIN))
261 return -EPERM;
262
263 br_stp_set_enabled(br, args[1]);
264 return 0;
265
266 case BRCTL_SET_BRIDGE_PRIORITY:
267 if (!capable(CAP_NET_ADMIN))
268 return -EPERM;
269
270 spin_lock_bh(&br->lock);
271 br_stp_set_bridge_priority(br, args[1]);
272 spin_unlock_bh(&br->lock);
273 return 0;
274
275 case BRCTL_SET_PORT_PRIORITY:
276 {
277 struct net_bridge_port *p;
278 int ret = 0;
279
280 if (!capable(CAP_NET_ADMIN))
281 return -EPERM;
282
283 if (args[2] >= (1<<(16-BR_PORT_BITS)))
284 return -ERANGE;
285
286 spin_lock_bh(&br->lock);
287 if ((p = br_get_port(br, args[1])) == NULL)
288 ret = -EINVAL;
289 else
290 br_stp_set_port_priority(p, args[2]);
291 spin_unlock_bh(&br->lock);
292 return ret;
293 }
294
295 case BRCTL_SET_PATH_COST:
296 {
297 struct net_bridge_port *p;
298 int ret = 0;
299
300 if (!capable(CAP_NET_ADMIN))
301 return -EPERM;
302
303 if ((p = br_get_port(br, args[1])) == NULL)
304 ret = -EINVAL;
305 else
306 br_stp_set_path_cost(p, args[2]);
307
308 return ret;
309 }
310
311 case BRCTL_GET_FDB_ENTRIES:
312 return get_fdb_entries(br, (void __user *)args[1],
313 args[2], args[3]);
314 }
315
316 return -EOPNOTSUPP;
317 }
318
old_deviceless(struct net * net,void __user * uarg)319 static int old_deviceless(struct net *net, void __user *uarg)
320 {
321 unsigned long args[3];
322
323 if (copy_from_user(args, uarg, sizeof(args)))
324 return -EFAULT;
325
326 switch (args[0]) {
327 case BRCTL_GET_VERSION:
328 return BRCTL_VERSION;
329
330 case BRCTL_GET_BRIDGES:
331 {
332 int *indices;
333 int ret = 0;
334
335 if (args[2] >= 2048)
336 return -ENOMEM;
337 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
338 if (indices == NULL)
339 return -ENOMEM;
340
341 args[2] = get_bridge_ifindices(net, indices, args[2]);
342
343 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
344 ? -EFAULT : args[2];
345
346 kfree(indices);
347 return ret;
348 }
349
350 case BRCTL_ADD_BRIDGE:
351 case BRCTL_DEL_BRIDGE:
352 {
353 char buf[IFNAMSIZ];
354
355 if (!capable(CAP_NET_ADMIN))
356 return -EPERM;
357
358 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
359 return -EFAULT;
360
361 buf[IFNAMSIZ-1] = 0;
362
363 if (args[0] == BRCTL_ADD_BRIDGE)
364 return br_add_bridge(net, buf);
365
366 return br_del_bridge(net, buf);
367 }
368 }
369
370 return -EOPNOTSUPP;
371 }
372
br_ioctl_deviceless_stub(struct net * net,unsigned int cmd,void __user * uarg)373 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
374 {
375 switch (cmd) {
376 case SIOCGIFBR:
377 case SIOCSIFBR:
378 return old_deviceless(net, uarg);
379
380 case SIOCBRADDBR:
381 case SIOCBRDELBR:
382 {
383 char buf[IFNAMSIZ];
384
385 if (!capable(CAP_NET_ADMIN))
386 return -EPERM;
387
388 if (copy_from_user(buf, uarg, IFNAMSIZ))
389 return -EFAULT;
390
391 buf[IFNAMSIZ-1] = 0;
392 if (cmd == SIOCBRADDBR)
393 return br_add_bridge(net, buf);
394
395 return br_del_bridge(net, buf);
396 }
397 }
398 return -EOPNOTSUPP;
399 }
400
br_dev_ioctl(struct net_device * dev,struct ifreq * rq,int cmd)401 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
402 {
403 struct net_bridge *br = netdev_priv(dev);
404
405 switch(cmd) {
406 case SIOCDEVPRIVATE:
407 return old_dev_ioctl(dev, rq, cmd);
408
409 case SIOCBRADDIF:
410 case SIOCBRDELIF:
411 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
412
413 }
414
415 br_debug(br, "Bridge does not support ioctl 0x%x\n", cmd);
416 return -EOPNOTSUPP;
417 }
418