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