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