xref: /openbmc/linux/net/bridge/br_ioctl.c (revision 8b235f2f)
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 *net = dev_net(br->dev);
89 	struct net_device *dev;
90 	int ret;
91 
92 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
93 		return -EPERM;
94 
95 	dev = __dev_get_by_index(net, ifindex);
96 	if (dev == NULL)
97 		return -EINVAL;
98 
99 	if (isadd)
100 		ret = br_add_if(br, dev);
101 	else
102 		ret = br_del_if(br, dev);
103 
104 	return ret;
105 }
106 
107 /*
108  * Legacy ioctl's through SIOCDEVPRIVATE
109  * This interface is deprecated because it was too difficult to
110  * to do the translation for 32/64bit ioctl compatibility.
111  */
112 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
113 {
114 	struct net_bridge *br = netdev_priv(dev);
115 	unsigned long args[4];
116 
117 	if (copy_from_user(args, rq->ifr_data, sizeof(args)))
118 		return -EFAULT;
119 
120 	switch (args[0]) {
121 	case BRCTL_ADD_IF:
122 	case BRCTL_DEL_IF:
123 		return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
124 
125 	case BRCTL_GET_BRIDGE_INFO:
126 	{
127 		struct __bridge_info b;
128 
129 		memset(&b, 0, sizeof(struct __bridge_info));
130 		rcu_read_lock();
131 		memcpy(&b.designated_root, &br->designated_root, 8);
132 		memcpy(&b.bridge_id, &br->bridge_id, 8);
133 		b.root_path_cost = br->root_path_cost;
134 		b.max_age = jiffies_to_clock_t(br->max_age);
135 		b.hello_time = jiffies_to_clock_t(br->hello_time);
136 		b.forward_delay = br->forward_delay;
137 		b.bridge_max_age = br->bridge_max_age;
138 		b.bridge_hello_time = br->bridge_hello_time;
139 		b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
140 		b.topology_change = br->topology_change;
141 		b.topology_change_detected = br->topology_change_detected;
142 		b.root_port = br->root_port;
143 
144 		b.stp_enabled = (br->stp_enabled != BR_NO_STP);
145 		b.ageing_time = jiffies_to_clock_t(br->ageing_time);
146 		b.hello_timer_value = br_timer_value(&br->hello_timer);
147 		b.tcn_timer_value = br_timer_value(&br->tcn_timer);
148 		b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
149 		b.gc_timer_value = br_timer_value(&br->gc_timer);
150 		rcu_read_unlock();
151 
152 		if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
153 			return -EFAULT;
154 
155 		return 0;
156 	}
157 
158 	case BRCTL_GET_PORT_LIST:
159 	{
160 		int num, *indices;
161 
162 		num = args[2];
163 		if (num < 0)
164 			return -EINVAL;
165 		if (num == 0)
166 			num = 256;
167 		if (num > BR_MAX_PORTS)
168 			num = BR_MAX_PORTS;
169 
170 		indices = kcalloc(num, sizeof(int), GFP_KERNEL);
171 		if (indices == NULL)
172 			return -ENOMEM;
173 
174 		get_port_ifindices(br, indices, num);
175 		if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
176 			num =  -EFAULT;
177 		kfree(indices);
178 		return num;
179 	}
180 
181 	case BRCTL_SET_BRIDGE_FORWARD_DELAY:
182 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
183 			return -EPERM;
184 
185 		return br_set_forward_delay(br, args[1]);
186 
187 	case BRCTL_SET_BRIDGE_HELLO_TIME:
188 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
189 			return -EPERM;
190 
191 		return br_set_hello_time(br, args[1]);
192 
193 	case BRCTL_SET_BRIDGE_MAX_AGE:
194 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
195 			return -EPERM;
196 
197 		return br_set_max_age(br, args[1]);
198 
199 	case BRCTL_SET_AGEING_TIME:
200 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
201 			return -EPERM;
202 
203 		br->ageing_time = clock_t_to_jiffies(args[1]);
204 		return 0;
205 
206 	case BRCTL_GET_PORT_INFO:
207 	{
208 		struct __port_info p;
209 		struct net_bridge_port *pt;
210 
211 		rcu_read_lock();
212 		if ((pt = br_get_port(br, args[2])) == NULL) {
213 			rcu_read_unlock();
214 			return -EINVAL;
215 		}
216 
217 		memset(&p, 0, sizeof(struct __port_info));
218 		memcpy(&p.designated_root, &pt->designated_root, 8);
219 		memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
220 		p.port_id = pt->port_id;
221 		p.designated_port = pt->designated_port;
222 		p.path_cost = pt->path_cost;
223 		p.designated_cost = pt->designated_cost;
224 		p.state = pt->state;
225 		p.top_change_ack = pt->topology_change_ack;
226 		p.config_pending = pt->config_pending;
227 		p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
228 		p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
229 		p.hold_timer_value = br_timer_value(&pt->hold_timer);
230 
231 		rcu_read_unlock();
232 
233 		if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
234 			return -EFAULT;
235 
236 		return 0;
237 	}
238 
239 	case BRCTL_SET_BRIDGE_STP_STATE:
240 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
241 			return -EPERM;
242 
243 		br_stp_set_enabled(br, args[1]);
244 		return 0;
245 
246 	case BRCTL_SET_BRIDGE_PRIORITY:
247 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
248 			return -EPERM;
249 
250 		br_stp_set_bridge_priority(br, args[1]);
251 		return 0;
252 
253 	case BRCTL_SET_PORT_PRIORITY:
254 	{
255 		struct net_bridge_port *p;
256 		int ret;
257 
258 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
259 			return -EPERM;
260 
261 		spin_lock_bh(&br->lock);
262 		if ((p = br_get_port(br, args[1])) == NULL)
263 			ret = -EINVAL;
264 		else
265 			ret = br_stp_set_port_priority(p, args[2]);
266 		spin_unlock_bh(&br->lock);
267 		return ret;
268 	}
269 
270 	case BRCTL_SET_PATH_COST:
271 	{
272 		struct net_bridge_port *p;
273 		int ret;
274 
275 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
276 			return -EPERM;
277 
278 		spin_lock_bh(&br->lock);
279 		if ((p = br_get_port(br, args[1])) == NULL)
280 			ret = -EINVAL;
281 		else
282 			ret = br_stp_set_path_cost(p, args[2]);
283 		spin_unlock_bh(&br->lock);
284 
285 		return ret;
286 	}
287 
288 	case BRCTL_GET_FDB_ENTRIES:
289 		return get_fdb_entries(br, (void __user *)args[1],
290 				       args[2], args[3]);
291 	}
292 
293 	return -EOPNOTSUPP;
294 }
295 
296 static int old_deviceless(struct net *net, void __user *uarg)
297 {
298 	unsigned long args[3];
299 
300 	if (copy_from_user(args, uarg, sizeof(args)))
301 		return -EFAULT;
302 
303 	switch (args[0]) {
304 	case BRCTL_GET_VERSION:
305 		return BRCTL_VERSION;
306 
307 	case BRCTL_GET_BRIDGES:
308 	{
309 		int *indices;
310 		int ret = 0;
311 
312 		if (args[2] >= 2048)
313 			return -ENOMEM;
314 		indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
315 		if (indices == NULL)
316 			return -ENOMEM;
317 
318 		args[2] = get_bridge_ifindices(net, indices, args[2]);
319 
320 		ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
321 			? -EFAULT : args[2];
322 
323 		kfree(indices);
324 		return ret;
325 	}
326 
327 	case BRCTL_ADD_BRIDGE:
328 	case BRCTL_DEL_BRIDGE:
329 	{
330 		char buf[IFNAMSIZ];
331 
332 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
333 			return -EPERM;
334 
335 		if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
336 			return -EFAULT;
337 
338 		buf[IFNAMSIZ-1] = 0;
339 
340 		if (args[0] == BRCTL_ADD_BRIDGE)
341 			return br_add_bridge(net, buf);
342 
343 		return br_del_bridge(net, buf);
344 	}
345 	}
346 
347 	return -EOPNOTSUPP;
348 }
349 
350 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
351 {
352 	switch (cmd) {
353 	case SIOCGIFBR:
354 	case SIOCSIFBR:
355 		return old_deviceless(net, uarg);
356 
357 	case SIOCBRADDBR:
358 	case SIOCBRDELBR:
359 	{
360 		char buf[IFNAMSIZ];
361 
362 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
363 			return -EPERM;
364 
365 		if (copy_from_user(buf, uarg, IFNAMSIZ))
366 			return -EFAULT;
367 
368 		buf[IFNAMSIZ-1] = 0;
369 		if (cmd == SIOCBRADDBR)
370 			return br_add_bridge(net, buf);
371 
372 		return br_del_bridge(net, buf);
373 	}
374 	}
375 	return -EOPNOTSUPP;
376 }
377 
378 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
379 {
380 	struct net_bridge *br = netdev_priv(dev);
381 
382 	switch (cmd) {
383 	case SIOCDEVPRIVATE:
384 		return old_dev_ioctl(dev, rq, cmd);
385 
386 	case SIOCBRADDIF:
387 	case SIOCBRDELIF:
388 		return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
389 
390 	}
391 
392 	br_debug(br, "Bridge does not support ioctl 0x%x\n", cmd);
393 	return -EOPNOTSUPP;
394 }
395