xref: /linux/net/bridge/br_sysfs_if.c (revision a3a4a816b4b194c45d0217e8b9e08b2639802cda)
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 #include <linux/sched/signal.h>
21 
22 #include "br_private.h"
23 
24 struct brport_attribute {
25 	struct attribute	attr;
26 	ssize_t (*show)(struct net_bridge_port *, char *);
27 	int (*store)(struct net_bridge_port *, unsigned long);
28 };
29 
30 #define BRPORT_ATTR(_name, _mode, _show, _store)		\
31 const struct brport_attribute brport_attr_##_name = { 	        \
32 	.attr = {.name = __stringify(_name), 			\
33 		 .mode = _mode },				\
34 	.show	= _show,					\
35 	.store	= _store,					\
36 };
37 
38 #define BRPORT_ATTR_FLAG(_name, _mask)				\
39 static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
40 {								\
41 	return sprintf(buf, "%d\n", !!(p->flags & _mask));	\
42 }								\
43 static int store_##_name(struct net_bridge_port *p, unsigned long v) \
44 {								\
45 	return store_flag(p, v, _mask);				\
46 }								\
47 static BRPORT_ATTR(_name, S_IRUGO | S_IWUSR,			\
48 		   show_##_name, store_##_name)
49 
50 static int store_flag(struct net_bridge_port *p, unsigned long v,
51 		      unsigned long mask)
52 {
53 	unsigned long flags;
54 
55 	flags = p->flags;
56 
57 	if (v)
58 		flags |= mask;
59 	else
60 		flags &= ~mask;
61 
62 	if (flags != p->flags) {
63 		p->flags = flags;
64 		br_port_flags_change(p, mask);
65 	}
66 	return 0;
67 }
68 
69 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
70 {
71 	return sprintf(buf, "%d\n", p->path_cost);
72 }
73 
74 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
75 		   show_path_cost, br_stp_set_path_cost);
76 
77 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
78 {
79 	return sprintf(buf, "%d\n", p->priority);
80 }
81 
82 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
83 			 show_priority, br_stp_set_port_priority);
84 
85 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
86 {
87 	return br_show_bridge_id(buf, &p->designated_root);
88 }
89 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
90 
91 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
92 {
93 	return br_show_bridge_id(buf, &p->designated_bridge);
94 }
95 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
96 
97 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
98 {
99 	return sprintf(buf, "%d\n", p->designated_port);
100 }
101 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
102 
103 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
104 {
105 	return sprintf(buf, "%d\n", p->designated_cost);
106 }
107 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
108 
109 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
110 {
111 	return sprintf(buf, "0x%x\n", p->port_id);
112 }
113 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
114 
115 static 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 
120 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
121 
122 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
123 {
124 	return sprintf(buf, "%d\n", p->topology_change_ack);
125 }
126 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
127 
128 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
129 {
130 	return sprintf(buf, "%d\n", p->config_pending);
131 }
132 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
133 
134 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
135 {
136 	return sprintf(buf, "%d\n", p->state);
137 }
138 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
139 
140 static 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 }
145 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
146 
147 static 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 }
152 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
153 
154 static 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 }
159 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
160 
161 static int store_flush(struct net_bridge_port *p, unsigned long v)
162 {
163 	br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
164 	return 0;
165 }
166 static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
167 
168 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
169 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
170 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
171 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
172 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
173 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
174 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
175 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
176 
177 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
178 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
179 {
180 	return sprintf(buf, "%d\n", p->multicast_router);
181 }
182 
183 static int store_multicast_router(struct net_bridge_port *p,
184 				      unsigned long v)
185 {
186 	return br_multicast_set_port_router(p, v);
187 }
188 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
189 		   store_multicast_router);
190 
191 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
192 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
193 #endif
194 
195 static const struct brport_attribute *brport_attrs[] = {
196 	&brport_attr_path_cost,
197 	&brport_attr_priority,
198 	&brport_attr_port_id,
199 	&brport_attr_port_no,
200 	&brport_attr_designated_root,
201 	&brport_attr_designated_bridge,
202 	&brport_attr_designated_port,
203 	&brport_attr_designated_cost,
204 	&brport_attr_state,
205 	&brport_attr_change_ack,
206 	&brport_attr_config_pending,
207 	&brport_attr_message_age_timer,
208 	&brport_attr_forward_delay_timer,
209 	&brport_attr_hold_timer,
210 	&brport_attr_flush,
211 	&brport_attr_hairpin_mode,
212 	&brport_attr_bpdu_guard,
213 	&brport_attr_root_block,
214 	&brport_attr_learning,
215 	&brport_attr_unicast_flood,
216 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
217 	&brport_attr_multicast_router,
218 	&brport_attr_multicast_fast_leave,
219 	&brport_attr_multicast_to_unicast,
220 #endif
221 	&brport_attr_proxyarp,
222 	&brport_attr_proxyarp_wifi,
223 	&brport_attr_multicast_flood,
224 	NULL
225 };
226 
227 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
228 #define to_brport(obj)	container_of(obj, struct net_bridge_port, kobj)
229 
230 static ssize_t brport_show(struct kobject *kobj,
231 			   struct attribute *attr, char *buf)
232 {
233 	struct brport_attribute *brport_attr = to_brport_attr(attr);
234 	struct net_bridge_port *p = to_brport(kobj);
235 
236 	return brport_attr->show(p, buf);
237 }
238 
239 static ssize_t brport_store(struct kobject *kobj,
240 			    struct attribute *attr,
241 			    const char *buf, size_t count)
242 {
243 	struct brport_attribute *brport_attr = to_brport_attr(attr);
244 	struct net_bridge_port *p = to_brport(kobj);
245 	ssize_t ret = -EINVAL;
246 	char *endp;
247 	unsigned long val;
248 
249 	if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
250 		return -EPERM;
251 
252 	val = simple_strtoul(buf, &endp, 0);
253 	if (endp != buf) {
254 		if (!rtnl_trylock())
255 			return restart_syscall();
256 		if (p->dev && p->br && brport_attr->store) {
257 			spin_lock_bh(&p->br->lock);
258 			ret = brport_attr->store(p, val);
259 			spin_unlock_bh(&p->br->lock);
260 			if (!ret) {
261 				br_ifinfo_notify(RTM_NEWLINK, p);
262 				ret = count;
263 			}
264 		}
265 		rtnl_unlock();
266 	}
267 	return ret;
268 }
269 
270 const struct sysfs_ops brport_sysfs_ops = {
271 	.show = brport_show,
272 	.store = brport_store,
273 };
274 
275 /*
276  * Add sysfs entries to ethernet device added to a bridge.
277  * Creates a brport subdirectory with bridge attributes.
278  * Puts symlink in bridge's brif subdirectory
279  */
280 int br_sysfs_addif(struct net_bridge_port *p)
281 {
282 	struct net_bridge *br = p->br;
283 	const struct brport_attribute **a;
284 	int err;
285 
286 	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
287 				SYSFS_BRIDGE_PORT_LINK);
288 	if (err)
289 		return err;
290 
291 	for (a = brport_attrs; *a; ++a) {
292 		err = sysfs_create_file(&p->kobj, &((*a)->attr));
293 		if (err)
294 			return err;
295 	}
296 
297 	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
298 	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
299 }
300 
301 /* Rename bridge's brif symlink */
302 int br_sysfs_renameif(struct net_bridge_port *p)
303 {
304 	struct net_bridge *br = p->br;
305 	int err;
306 
307 	/* If a rename fails, the rollback will cause another
308 	 * rename call with the existing name.
309 	 */
310 	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
311 		return 0;
312 
313 	err = sysfs_rename_link(br->ifobj, &p->kobj,
314 				p->sysfs_name, p->dev->name);
315 	if (err)
316 		netdev_notice(br->dev, "unable to rename link %s to %s",
317 			      p->sysfs_name, p->dev->name);
318 	else
319 		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
320 
321 	return err;
322 }
323