xref: /openbmc/linux/net/bridge/br_ioctl.c (revision 367b8112)
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/times.h>
19 #include <net/net_namespace.h>
20 #include <asm/uaccess.h>
21 #include "br_private.h"
22 
23 /* called with RTNL */
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 	for_each_netdev(net, dev) {
30 		if (i >= num)
31 			break;
32 		if (dev->priv_flags & IFF_EBRIDGE)
33 			indices[i++] = dev->ifindex;
34 	}
35 
36 	return i;
37 }
38 
39 /* called with RTNL */
40 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num)
41 {
42 	struct net_bridge_port *p;
43 
44 	list_for_each_entry(p, &br->port_list, list) {
45 		if (p->port_no < num)
46 			ifindices[p->port_no] = p->dev->ifindex;
47 	}
48 }
49 
50 /*
51  * Format up to a page worth of forwarding table entries
52  * userbuf -- where to copy result
53  * maxnum  -- maximum number of entries desired
54  *            (limited to a page for sanity)
55  * offset  -- number of records to skip
56  */
57 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
58 			   unsigned long maxnum, unsigned long offset)
59 {
60 	int num;
61 	void *buf;
62 	size_t size;
63 
64 	/* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */
65 	if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry))
66 		maxnum = PAGE_SIZE/sizeof(struct __fdb_entry);
67 
68 	size = maxnum * sizeof(struct __fdb_entry);
69 
70 	buf = kmalloc(size, GFP_USER);
71 	if (!buf)
72 		return -ENOMEM;
73 
74 	num = br_fdb_fillbuf(br, buf, maxnum, offset);
75 	if (num > 0) {
76 		if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry)))
77 			num = -EFAULT;
78 	}
79 	kfree(buf);
80 
81 	return num;
82 }
83 
84 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
85 {
86 	struct net_device *dev;
87 	int ret;
88 
89 	if (!capable(CAP_NET_ADMIN))
90 		return -EPERM;
91 
92 	dev = dev_get_by_index(dev_net(br->dev), ifindex);
93 	if (dev == NULL)
94 		return -EINVAL;
95 
96 	if (isadd)
97 		ret = br_add_if(br, dev);
98 	else
99 		ret = br_del_if(br, dev);
100 
101 	dev_put(dev);
102 	return ret;
103 }
104 
105 /*
106  * Legacy ioctl's through SIOCDEVPRIVATE
107  * This interface is deprecated because it was too difficult to
108  * to do the translation for 32/64bit ioctl compatability.
109  */
110 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
111 {
112 	struct net_bridge *br = netdev_priv(dev);
113 	unsigned long args[4];
114 
115 	if (copy_from_user(args, rq->ifr_data, sizeof(args)))
116 		return -EFAULT;
117 
118 	switch (args[0]) {
119 	case BRCTL_ADD_IF:
120 	case BRCTL_DEL_IF:
121 		return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
122 
123 	case BRCTL_GET_BRIDGE_INFO:
124 	{
125 		struct __bridge_info b;
126 
127 		memset(&b, 0, sizeof(struct __bridge_info));
128 		rcu_read_lock();
129 		memcpy(&b.designated_root, &br->designated_root, 8);
130 		memcpy(&b.bridge_id, &br->bridge_id, 8);
131 		b.root_path_cost = br->root_path_cost;
132 		b.max_age = jiffies_to_clock_t(br->max_age);
133 		b.hello_time = jiffies_to_clock_t(br->hello_time);
134 		b.forward_delay = br->forward_delay;
135 		b.bridge_max_age = br->bridge_max_age;
136 		b.bridge_hello_time = br->bridge_hello_time;
137 		b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
138 		b.topology_change = br->topology_change;
139 		b.topology_change_detected = br->topology_change_detected;
140 		b.root_port = br->root_port;
141 
142 		b.stp_enabled = (br->stp_enabled != BR_NO_STP);
143 		b.ageing_time = jiffies_to_clock_t(br->ageing_time);
144 		b.hello_timer_value = br_timer_value(&br->hello_timer);
145 		b.tcn_timer_value = br_timer_value(&br->tcn_timer);
146 		b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
147 		b.gc_timer_value = br_timer_value(&br->gc_timer);
148 		rcu_read_unlock();
149 
150 		if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
151 			return -EFAULT;
152 
153 		return 0;
154 	}
155 
156 	case BRCTL_GET_PORT_LIST:
157 	{
158 		int num, *indices;
159 
160 		num = args[2];
161 		if (num < 0)
162 			return -EINVAL;
163 		if (num == 0)
164 			num = 256;
165 		if (num > BR_MAX_PORTS)
166 			num = BR_MAX_PORTS;
167 
168 		indices = kcalloc(num, sizeof(int), GFP_KERNEL);
169 		if (indices == NULL)
170 			return -ENOMEM;
171 
172 		get_port_ifindices(br, indices, num);
173 		if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
174 			num =  -EFAULT;
175 		kfree(indices);
176 		return num;
177 	}
178 
179 	case BRCTL_SET_BRIDGE_FORWARD_DELAY:
180 		if (!capable(CAP_NET_ADMIN))
181 			return -EPERM;
182 
183 		spin_lock_bh(&br->lock);
184 		br->bridge_forward_delay = clock_t_to_jiffies(args[1]);
185 		if (br_is_root_bridge(br))
186 			br->forward_delay = br->bridge_forward_delay;
187 		spin_unlock_bh(&br->lock);
188 		return 0;
189 
190 	case BRCTL_SET_BRIDGE_HELLO_TIME:
191 	{
192 		unsigned long t = clock_t_to_jiffies(args[1]);
193 		if (!capable(CAP_NET_ADMIN))
194 			return -EPERM;
195 
196 		if (t < HZ)
197 			return -EINVAL;
198 
199 		spin_lock_bh(&br->lock);
200 		br->bridge_hello_time = t;
201 		if (br_is_root_bridge(br))
202 			br->hello_time = br->bridge_hello_time;
203 		spin_unlock_bh(&br->lock);
204 		return 0;
205 	}
206 
207 	case BRCTL_SET_BRIDGE_MAX_AGE:
208 		if (!capable(CAP_NET_ADMIN))
209 			return -EPERM;
210 
211 		spin_lock_bh(&br->lock);
212 		br->bridge_max_age = clock_t_to_jiffies(args[1]);
213 		if (br_is_root_bridge(br))
214 			br->max_age = br->bridge_max_age;
215 		spin_unlock_bh(&br->lock);
216 		return 0;
217 
218 	case BRCTL_SET_AGEING_TIME:
219 		if (!capable(CAP_NET_ADMIN))
220 			return -EPERM;
221 
222 		br->ageing_time = clock_t_to_jiffies(args[1]);
223 		return 0;
224 
225 	case BRCTL_GET_PORT_INFO:
226 	{
227 		struct __port_info p;
228 		struct net_bridge_port *pt;
229 
230 		rcu_read_lock();
231 		if ((pt = br_get_port(br, args[2])) == NULL) {
232 			rcu_read_unlock();
233 			return -EINVAL;
234 		}
235 
236 		memset(&p, 0, sizeof(struct __port_info));
237 		memcpy(&p.designated_root, &pt->designated_root, 8);
238 		memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
239 		p.port_id = pt->port_id;
240 		p.designated_port = pt->designated_port;
241 		p.path_cost = pt->path_cost;
242 		p.designated_cost = pt->designated_cost;
243 		p.state = pt->state;
244 		p.top_change_ack = pt->topology_change_ack;
245 		p.config_pending = pt->config_pending;
246 		p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
247 		p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
248 		p.hold_timer_value = br_timer_value(&pt->hold_timer);
249 
250 		rcu_read_unlock();
251 
252 		if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
253 			return -EFAULT;
254 
255 		return 0;
256 	}
257 
258 	case BRCTL_SET_BRIDGE_STP_STATE:
259 		if (!capable(CAP_NET_ADMIN))
260 			return -EPERM;
261 
262 		br_stp_set_enabled(br, args[1]);
263 		return 0;
264 
265 	case BRCTL_SET_BRIDGE_PRIORITY:
266 		if (!capable(CAP_NET_ADMIN))
267 			return -EPERM;
268 
269 		spin_lock_bh(&br->lock);
270 		br_stp_set_bridge_priority(br, args[1]);
271 		spin_unlock_bh(&br->lock);
272 		return 0;
273 
274 	case BRCTL_SET_PORT_PRIORITY:
275 	{
276 		struct net_bridge_port *p;
277 		int ret = 0;
278 
279 		if (!capable(CAP_NET_ADMIN))
280 			return -EPERM;
281 
282 		if (args[2] >= (1<<(16-BR_PORT_BITS)))
283 			return -ERANGE;
284 
285 		spin_lock_bh(&br->lock);
286 		if ((p = br_get_port(br, args[1])) == NULL)
287 			ret = -EINVAL;
288 		else
289 			br_stp_set_port_priority(p, args[2]);
290 		spin_unlock_bh(&br->lock);
291 		return ret;
292 	}
293 
294 	case BRCTL_SET_PATH_COST:
295 	{
296 		struct net_bridge_port *p;
297 		int ret = 0;
298 
299 		if (!capable(CAP_NET_ADMIN))
300 			return -EPERM;
301 
302 		if ((p = br_get_port(br, args[1])) == NULL)
303 			ret = -EINVAL;
304 		else
305 			br_stp_set_path_cost(p, args[2]);
306 
307 		return ret;
308 	}
309 
310 	case BRCTL_GET_FDB_ENTRIES:
311 		return get_fdb_entries(br, (void __user *)args[1],
312 				       args[2], args[3]);
313 	}
314 
315 	return -EOPNOTSUPP;
316 }
317 
318 static int old_deviceless(struct net *net, void __user *uarg)
319 {
320 	unsigned long args[3];
321 
322 	if (copy_from_user(args, uarg, sizeof(args)))
323 		return -EFAULT;
324 
325 	switch (args[0]) {
326 	case BRCTL_GET_VERSION:
327 		return BRCTL_VERSION;
328 
329 	case BRCTL_GET_BRIDGES:
330 	{
331 		int *indices;
332 		int ret = 0;
333 
334 		if (args[2] >= 2048)
335 			return -ENOMEM;
336 		indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
337 		if (indices == NULL)
338 			return -ENOMEM;
339 
340 		args[2] = get_bridge_ifindices(net, indices, args[2]);
341 
342 		ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
343 			? -EFAULT : args[2];
344 
345 		kfree(indices);
346 		return ret;
347 	}
348 
349 	case BRCTL_ADD_BRIDGE:
350 	case BRCTL_DEL_BRIDGE:
351 	{
352 		char buf[IFNAMSIZ];
353 
354 		if (!capable(CAP_NET_ADMIN))
355 			return -EPERM;
356 
357 		if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
358 			return -EFAULT;
359 
360 		buf[IFNAMSIZ-1] = 0;
361 
362 		if (args[0] == BRCTL_ADD_BRIDGE)
363 			return br_add_bridge(net, buf);
364 
365 		return br_del_bridge(net, buf);
366 	}
367 	}
368 
369 	return -EOPNOTSUPP;
370 }
371 
372 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
373 {
374 	switch (cmd) {
375 	case SIOCGIFBR:
376 	case SIOCSIFBR:
377 		return old_deviceless(net, uarg);
378 
379 	case SIOCBRADDBR:
380 	case SIOCBRDELBR:
381 	{
382 		char buf[IFNAMSIZ];
383 
384 		if (!capable(CAP_NET_ADMIN))
385 			return -EPERM;
386 
387 		if (copy_from_user(buf, uarg, IFNAMSIZ))
388 			return -EFAULT;
389 
390 		buf[IFNAMSIZ-1] = 0;
391 		if (cmd == SIOCBRADDBR)
392 			return br_add_bridge(net, buf);
393 
394 		return br_del_bridge(net, buf);
395 	}
396 	}
397 	return -EOPNOTSUPP;
398 }
399 
400 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
401 {
402 	struct net_bridge *br = netdev_priv(dev);
403 
404 	switch(cmd) {
405 	case SIOCDEVPRIVATE:
406 		return old_dev_ioctl(dev, rq, cmd);
407 
408 	case SIOCBRADDIF:
409 	case SIOCBRDELIF:
410 		return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
411 
412 	}
413 
414 	pr_debug("Bridge does not support ioctl 0x%x\n", cmd);
415 	return -EOPNOTSUPP;
416 }
417