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 */
25static 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 */
41static 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 */
58static 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 */
86static 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 */
112static 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		spin_lock_bh(&br->lock);
251		br_stp_set_bridge_priority(br, args[1]);
252		spin_unlock_bh(&br->lock);
253		return 0;
254
255	case BRCTL_SET_PORT_PRIORITY:
256	{
257		struct net_bridge_port *p;
258		int ret;
259
260		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
261			return -EPERM;
262
263		spin_lock_bh(&br->lock);
264		if ((p = br_get_port(br, args[1])) == NULL)
265			ret = -EINVAL;
266		else
267			ret = br_stp_set_port_priority(p, args[2]);
268		spin_unlock_bh(&br->lock);
269		return ret;
270	}
271
272	case BRCTL_SET_PATH_COST:
273	{
274		struct net_bridge_port *p;
275		int ret;
276
277		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
278			return -EPERM;
279
280		spin_lock_bh(&br->lock);
281		if ((p = br_get_port(br, args[1])) == NULL)
282			ret = -EINVAL;
283		else
284			ret = br_stp_set_path_cost(p, args[2]);
285		spin_unlock_bh(&br->lock);
286
287		return ret;
288	}
289
290	case BRCTL_GET_FDB_ENTRIES:
291		return get_fdb_entries(br, (void __user *)args[1],
292				       args[2], args[3]);
293	}
294
295	return -EOPNOTSUPP;
296}
297
298static int old_deviceless(struct net *net, void __user *uarg)
299{
300	unsigned long args[3];
301
302	if (copy_from_user(args, uarg, sizeof(args)))
303		return -EFAULT;
304
305	switch (args[0]) {
306	case BRCTL_GET_VERSION:
307		return BRCTL_VERSION;
308
309	case BRCTL_GET_BRIDGES:
310	{
311		int *indices;
312		int ret = 0;
313
314		if (args[2] >= 2048)
315			return -ENOMEM;
316		indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
317		if (indices == NULL)
318			return -ENOMEM;
319
320		args[2] = get_bridge_ifindices(net, indices, args[2]);
321
322		ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
323			? -EFAULT : args[2];
324
325		kfree(indices);
326		return ret;
327	}
328
329	case BRCTL_ADD_BRIDGE:
330	case BRCTL_DEL_BRIDGE:
331	{
332		char buf[IFNAMSIZ];
333
334		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
335			return -EPERM;
336
337		if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
338			return -EFAULT;
339
340		buf[IFNAMSIZ-1] = 0;
341
342		if (args[0] == BRCTL_ADD_BRIDGE)
343			return br_add_bridge(net, buf);
344
345		return br_del_bridge(net, buf);
346	}
347	}
348
349	return -EOPNOTSUPP;
350}
351
352int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
353{
354	switch (cmd) {
355	case SIOCGIFBR:
356	case SIOCSIFBR:
357		return old_deviceless(net, uarg);
358
359	case SIOCBRADDBR:
360	case SIOCBRDELBR:
361	{
362		char buf[IFNAMSIZ];
363
364		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
365			return -EPERM;
366
367		if (copy_from_user(buf, uarg, IFNAMSIZ))
368			return -EFAULT;
369
370		buf[IFNAMSIZ-1] = 0;
371		if (cmd == SIOCBRADDBR)
372			return br_add_bridge(net, buf);
373
374		return br_del_bridge(net, buf);
375	}
376	}
377	return -EOPNOTSUPP;
378}
379
380int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
381{
382	struct net_bridge *br = netdev_priv(dev);
383
384	switch(cmd) {
385	case SIOCDEVPRIVATE:
386		return old_dev_ioctl(dev, rq, cmd);
387
388	case SIOCBRADDIF:
389	case SIOCBRDELIF:
390		return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
391
392	}
393
394	br_debug(br, "Bridge does not support ioctl 0x%x\n", cmd);
395	return -EOPNOTSUPP;
396}
397