xref: /openbmc/linux/net/bridge/br_ioctl.c (revision 95e9fd10)
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 */
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 
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  */
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 
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 		return br_set_forward_delay(br, args[1]);
185 
186 	case BRCTL_SET_BRIDGE_HELLO_TIME:
187 		if (!capable(CAP_NET_ADMIN))
188 			return -EPERM;
189 
190 		return br_set_hello_time(br, args[1]);
191 
192 	case BRCTL_SET_BRIDGE_MAX_AGE:
193 		if (!capable(CAP_NET_ADMIN))
194 			return -EPERM;
195 
196 		return br_set_max_age(br, args[1]);
197 
198 	case BRCTL_SET_AGEING_TIME:
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));
217 		memcpy(&p.designated_root, &pt->designated_root, 8);
218 		memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
219 		p.port_id = pt->port_id;
220 		p.designated_port = pt->designated_port;
221 		p.path_cost = pt->path_cost;
222 		p.designated_cost = pt->designated_cost;
223 		p.state = pt->state;
224 		p.top_change_ack = pt->topology_change_ack;
225 		p.config_pending = pt->config_pending;
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 
238 	case BRCTL_SET_BRIDGE_STP_STATE:
239 		if (!capable(CAP_NET_ADMIN))
240 			return -EPERM;
241 
242 		br_stp_set_enabled(br, args[1]);
243 		return 0;
244 
245 	case BRCTL_SET_BRIDGE_PRIORITY:
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 
254 	case BRCTL_SET_PORT_PRIORITY:
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 
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 
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 }
396