Linux Kernel  3.7.1
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br_ioctl.c
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1 /*
2  * Ioctl handler
3  * Linux ethernet bridge
4  *
5  * Authors:
6  * Lennert Buytenhek <[email protected]>
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 */
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 */
41 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num)
42 {
43  struct net_bridge_port *p;
44 
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  */
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 */
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  */
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 
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 
181  if (!capable(CAP_NET_ADMIN))
182  return -EPERM;
183 
184  return br_set_forward_delay(br, args[1]);
185 
187  if (!capable(CAP_NET_ADMIN))
188  return -EPERM;
189 
190  return br_set_hello_time(br, args[1]);
191 
193  if (!capable(CAP_NET_ADMIN))
194  return -EPERM;
195 
196  return br_set_max_age(br, args[1]);
197 
199  if (!capable(CAP_NET_ADMIN))
200  return -EPERM;
201 
202  br->ageing_time = clock_t_to_jiffies(args[1]);
203  return 0;
204 
205  case BRCTL_GET_PORT_INFO:
206  {
207  struct __port_info p;
208  struct net_bridge_port *pt;
209 
210  rcu_read_lock();
211  if ((pt = br_get_port(br, args[2])) == NULL) {
212  rcu_read_unlock();
213  return -EINVAL;
214  }
215 
216  memset(&p, 0, sizeof(struct __port_info));
219  p.port_id = pt->port_id;
221  p.path_cost = pt->path_cost;
223  p.state = pt->state;
224  p.top_change_ack = pt->topology_change_ack;
226  p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
227  p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
228  p.hold_timer_value = br_timer_value(&pt->hold_timer);
229 
230  rcu_read_unlock();
231 
232  if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
233  return -EFAULT;
234 
235  return 0;
236  }
237 
239  if (!capable(CAP_NET_ADMIN))
240  return -EPERM;
241 
242  br_stp_set_enabled(br, args[1]);
243  return 0;
244 
246  if (!capable(CAP_NET_ADMIN))
247  return -EPERM;
248 
249  spin_lock_bh(&br->lock);
250  br_stp_set_bridge_priority(br, args[1]);
251  spin_unlock_bh(&br->lock);
252  return 0;
253 
255  {
256  struct net_bridge_port *p;
257  int ret;
258 
259  if (!capable(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 (!capable(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 
290  return get_fdb_entries(br, (void __user *)args[1],
291  args[2], args[3]);
292  }
293 
294  return -EOPNOTSUPP;
295 }
296 
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 (!capable(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 
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 (!capable(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 
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 }