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