1/*
2 *	Sysfs attributes of bridge ports
3 *	Linux ethernet bridge
4 *
5 *	Authors:
6 *	Stephen Hemminger		<shemminger@osdl.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/netdevice.h>
17#include <linux/if_bridge.h>
18#include <linux/rtnetlink.h>
19#include <linux/spinlock.h>
20
21#include "br_private.h"
22
23struct brport_attribute {
24	struct attribute	attr;
25	ssize_t (*show)(struct net_bridge_port *, char *);
26	int (*store)(struct net_bridge_port *, unsigned long);
27};
28
29#define BRPORT_ATTR(_name, _mode, _show, _store)		\
30const struct brport_attribute brport_attr_##_name = { 	        \
31	.attr = {.name = __stringify(_name), 			\
32		 .mode = _mode },				\
33	.show	= _show,					\
34	.store	= _store,					\
35};
36
37#define BRPORT_ATTR_FLAG(_name, _mask)				\
38static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
39{								\
40	return sprintf(buf, "%d\n", !!(p->flags & _mask));	\
41}								\
42static int store_##_name(struct net_bridge_port *p, unsigned long v) \
43{								\
44	return store_flag(p, v, _mask);				\
45}								\
46static BRPORT_ATTR(_name, S_IRUGO | S_IWUSR,			\
47		   show_##_name, store_##_name)
48
49static int store_flag(struct net_bridge_port *p, unsigned long v,
50		      unsigned long mask)
51{
52	unsigned long flags;
53
54	flags = p->flags;
55
56	if (v)
57		flags |= mask;
58	else
59		flags &= ~mask;
60
61	if (flags != p->flags) {
62		p->flags = flags;
63		br_port_flags_change(p, mask);
64		br_ifinfo_notify(RTM_NEWLINK, p);
65	}
66	return 0;
67}
68
69static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
70{
71	return sprintf(buf, "%d\n", p->path_cost);
72}
73
74static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
75		   show_path_cost, br_stp_set_path_cost);
76
77static ssize_t show_priority(struct net_bridge_port *p, char *buf)
78{
79	return sprintf(buf, "%d\n", p->priority);
80}
81
82static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
83			 show_priority, br_stp_set_port_priority);
84
85static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
86{
87	return br_show_bridge_id(buf, &p->designated_root);
88}
89static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
90
91static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
92{
93	return br_show_bridge_id(buf, &p->designated_bridge);
94}
95static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
96
97static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
98{
99	return sprintf(buf, "%d\n", p->designated_port);
100}
101static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
102
103static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
104{
105	return sprintf(buf, "%d\n", p->designated_cost);
106}
107static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
108
109static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
110{
111	return sprintf(buf, "0x%x\n", p->port_id);
112}
113static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
114
115static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
116{
117	return sprintf(buf, "0x%x\n", p->port_no);
118}
119
120static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
121
122static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
123{
124	return sprintf(buf, "%d\n", p->topology_change_ack);
125}
126static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
127
128static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
129{
130	return sprintf(buf, "%d\n", p->config_pending);
131}
132static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
133
134static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
135{
136	return sprintf(buf, "%d\n", p->state);
137}
138static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
139
140static ssize_t show_message_age_timer(struct net_bridge_port *p,
141					    char *buf)
142{
143	return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
144}
145static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
146
147static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
148					    char *buf)
149{
150	return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
151}
152static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
153
154static ssize_t show_hold_timer(struct net_bridge_port *p,
155					    char *buf)
156{
157	return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
158}
159static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
160
161static int store_flush(struct net_bridge_port *p, unsigned long v)
162{
163	br_fdb_delete_by_port(p->br, p, 0); // Don't delete local entry
164	return 0;
165}
166static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
167
168BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
169BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
170BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
171BRPORT_ATTR_FLAG(learning, BR_LEARNING);
172BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
173
174#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
175static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
176{
177	return sprintf(buf, "%d\n", p->multicast_router);
178}
179
180static int store_multicast_router(struct net_bridge_port *p,
181				      unsigned long v)
182{
183	return br_multicast_set_port_router(p, v);
184}
185static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
186		   store_multicast_router);
187
188BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
189#endif
190
191static const struct brport_attribute *brport_attrs[] = {
192	&brport_attr_path_cost,
193	&brport_attr_priority,
194	&brport_attr_port_id,
195	&brport_attr_port_no,
196	&brport_attr_designated_root,
197	&brport_attr_designated_bridge,
198	&brport_attr_designated_port,
199	&brport_attr_designated_cost,
200	&brport_attr_state,
201	&brport_attr_change_ack,
202	&brport_attr_config_pending,
203	&brport_attr_message_age_timer,
204	&brport_attr_forward_delay_timer,
205	&brport_attr_hold_timer,
206	&brport_attr_flush,
207	&brport_attr_hairpin_mode,
208	&brport_attr_bpdu_guard,
209	&brport_attr_root_block,
210	&brport_attr_learning,
211	&brport_attr_unicast_flood,
212#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
213	&brport_attr_multicast_router,
214	&brport_attr_multicast_fast_leave,
215#endif
216	NULL
217};
218
219#define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
220#define to_brport(obj)	container_of(obj, struct net_bridge_port, kobj)
221
222static ssize_t brport_show(struct kobject *kobj,
223			   struct attribute *attr, char *buf)
224{
225	struct brport_attribute *brport_attr = to_brport_attr(attr);
226	struct net_bridge_port *p = to_brport(kobj);
227
228	return brport_attr->show(p, buf);
229}
230
231static ssize_t brport_store(struct kobject *kobj,
232			    struct attribute *attr,
233			    const char *buf, size_t count)
234{
235	struct brport_attribute *brport_attr = to_brport_attr(attr);
236	struct net_bridge_port *p = to_brport(kobj);
237	ssize_t ret = -EINVAL;
238	char *endp;
239	unsigned long val;
240
241	if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
242		return -EPERM;
243
244	val = simple_strtoul(buf, &endp, 0);
245	if (endp != buf) {
246		if (!rtnl_trylock())
247			return restart_syscall();
248		if (p->dev && p->br && brport_attr->store) {
249			spin_lock_bh(&p->br->lock);
250			ret = brport_attr->store(p, val);
251			spin_unlock_bh(&p->br->lock);
252			if (ret == 0)
253				ret = count;
254		}
255		rtnl_unlock();
256	}
257	return ret;
258}
259
260const struct sysfs_ops brport_sysfs_ops = {
261	.show = brport_show,
262	.store = brport_store,
263};
264
265/*
266 * Add sysfs entries to ethernet device added to a bridge.
267 * Creates a brport subdirectory with bridge attributes.
268 * Puts symlink in bridge's brif subdirectory
269 */
270int br_sysfs_addif(struct net_bridge_port *p)
271{
272	struct net_bridge *br = p->br;
273	const struct brport_attribute **a;
274	int err;
275
276	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
277				SYSFS_BRIDGE_PORT_LINK);
278	if (err)
279		return err;
280
281	for (a = brport_attrs; *a; ++a) {
282		err = sysfs_create_file(&p->kobj, &((*a)->attr));
283		if (err)
284			return err;
285	}
286
287	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
288	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
289}
290
291/* Rename bridge's brif symlink */
292int br_sysfs_renameif(struct net_bridge_port *p)
293{
294	struct net_bridge *br = p->br;
295	int err;
296
297	/* If a rename fails, the rollback will cause another
298	 * rename call with the existing name.
299	 */
300	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
301		return 0;
302
303	err = sysfs_rename_link(br->ifobj, &p->kobj,
304				p->sysfs_name, p->dev->name);
305	if (err)
306		netdev_notice(br->dev, "unable to rename link %s to %s",
307			      p->sysfs_name, p->dev->name);
308	else
309		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
310
311	return err;
312}
313