xref: /openbmc/linux/net/bridge/br_sysfs_if.c (revision 37744fee)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Sysfs attributes of bridge ports
4  *	Linux ethernet bridge
5  *
6  *	Authors:
7  *	Stephen Hemminger		<shemminger@osdl.org>
8  */
9 
10 #include <linux/capability.h>
11 #include <linux/kernel.h>
12 #include <linux/netdevice.h>
13 #include <linux/if_bridge.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/spinlock.h>
16 #include <linux/sched/signal.h>
17 
18 #include "br_private.h"
19 
20 struct brport_attribute {
21 	struct attribute	attr;
22 	ssize_t (*show)(struct net_bridge_port *, char *);
23 	int (*store)(struct net_bridge_port *, unsigned long);
24 	int (*store_raw)(struct net_bridge_port *, char *);
25 };
26 
27 #define BRPORT_ATTR_RAW(_name, _mode, _show, _store)			\
28 const struct brport_attribute brport_attr_##_name = {			\
29 	.attr		= {.name = __stringify(_name),			\
30 			   .mode = _mode },				\
31 	.show		= _show,					\
32 	.store_raw	= _store,					\
33 };
34 
35 #define BRPORT_ATTR(_name, _mode, _show, _store)		\
36 const struct brport_attribute brport_attr_##_name = { 	        \
37 	.attr = {.name = __stringify(_name), 			\
38 		 .mode = _mode },				\
39 	.show	= _show,					\
40 	.store	= _store,					\
41 };
42 
43 #define BRPORT_ATTR_FLAG(_name, _mask)				\
44 static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
45 {								\
46 	return sprintf(buf, "%d\n", !!(p->flags & _mask));	\
47 }								\
48 static int store_##_name(struct net_bridge_port *p, unsigned long v) \
49 {								\
50 	return store_flag(p, v, _mask);				\
51 }								\
52 static BRPORT_ATTR(_name, 0644,					\
53 		   show_##_name, store_##_name)
54 
55 static int store_flag(struct net_bridge_port *p, unsigned long v,
56 		      unsigned long mask)
57 {
58 	unsigned long flags;
59 
60 	flags = p->flags;
61 
62 	if (v)
63 		flags |= mask;
64 	else
65 		flags &= ~mask;
66 
67 	if (flags != p->flags) {
68 		p->flags = flags;
69 		br_port_flags_change(p, mask);
70 	}
71 	return 0;
72 }
73 
74 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
75 {
76 	return sprintf(buf, "%d\n", p->path_cost);
77 }
78 
79 static BRPORT_ATTR(path_cost, 0644,
80 		   show_path_cost, br_stp_set_path_cost);
81 
82 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
83 {
84 	return sprintf(buf, "%d\n", p->priority);
85 }
86 
87 static BRPORT_ATTR(priority, 0644,
88 			 show_priority, br_stp_set_port_priority);
89 
90 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
91 {
92 	return br_show_bridge_id(buf, &p->designated_root);
93 }
94 static BRPORT_ATTR(designated_root, 0444, show_designated_root, NULL);
95 
96 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
97 {
98 	return br_show_bridge_id(buf, &p->designated_bridge);
99 }
100 static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL);
101 
102 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
103 {
104 	return sprintf(buf, "%d\n", p->designated_port);
105 }
106 static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL);
107 
108 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
109 {
110 	return sprintf(buf, "%d\n", p->designated_cost);
111 }
112 static BRPORT_ATTR(designated_cost, 0444, show_designated_cost, NULL);
113 
114 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
115 {
116 	return sprintf(buf, "0x%x\n", p->port_id);
117 }
118 static BRPORT_ATTR(port_id, 0444, show_port_id, NULL);
119 
120 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
121 {
122 	return sprintf(buf, "0x%x\n", p->port_no);
123 }
124 
125 static BRPORT_ATTR(port_no, 0444, show_port_no, NULL);
126 
127 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
128 {
129 	return sprintf(buf, "%d\n", p->topology_change_ack);
130 }
131 static BRPORT_ATTR(change_ack, 0444, show_change_ack, NULL);
132 
133 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
134 {
135 	return sprintf(buf, "%d\n", p->config_pending);
136 }
137 static BRPORT_ATTR(config_pending, 0444, show_config_pending, NULL);
138 
139 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
140 {
141 	return sprintf(buf, "%d\n", p->state);
142 }
143 static BRPORT_ATTR(state, 0444, show_port_state, NULL);
144 
145 static ssize_t show_message_age_timer(struct net_bridge_port *p,
146 					    char *buf)
147 {
148 	return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
149 }
150 static BRPORT_ATTR(message_age_timer, 0444, show_message_age_timer, NULL);
151 
152 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
153 					    char *buf)
154 {
155 	return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
156 }
157 static BRPORT_ATTR(forward_delay_timer, 0444, show_forward_delay_timer, NULL);
158 
159 static ssize_t show_hold_timer(struct net_bridge_port *p,
160 					    char *buf)
161 {
162 	return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
163 }
164 static BRPORT_ATTR(hold_timer, 0444, show_hold_timer, NULL);
165 
166 static int store_flush(struct net_bridge_port *p, unsigned long v)
167 {
168 	br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
169 	return 0;
170 }
171 static BRPORT_ATTR(flush, 0200, NULL, store_flush);
172 
173 static ssize_t show_group_fwd_mask(struct net_bridge_port *p, char *buf)
174 {
175 	return sprintf(buf, "%#x\n", p->group_fwd_mask);
176 }
177 
178 static int store_group_fwd_mask(struct net_bridge_port *p,
179 				unsigned long v)
180 {
181 	if (v & BR_GROUPFWD_MACPAUSE)
182 		return -EINVAL;
183 	p->group_fwd_mask = v;
184 
185 	return 0;
186 }
187 static BRPORT_ATTR(group_fwd_mask, 0644, show_group_fwd_mask,
188 		   store_group_fwd_mask);
189 
190 static ssize_t show_backup_port(struct net_bridge_port *p, char *buf)
191 {
192 	struct net_bridge_port *backup_p;
193 	int ret = 0;
194 
195 	rcu_read_lock();
196 	backup_p = rcu_dereference(p->backup_port);
197 	if (backup_p)
198 		ret = sprintf(buf, "%s\n", backup_p->dev->name);
199 	rcu_read_unlock();
200 
201 	return ret;
202 }
203 
204 static int store_backup_port(struct net_bridge_port *p, char *buf)
205 {
206 	struct net_device *backup_dev = NULL;
207 	char *nl = strchr(buf, '\n');
208 
209 	if (nl)
210 		*nl = '\0';
211 
212 	if (strlen(buf) > 0) {
213 		backup_dev = __dev_get_by_name(dev_net(p->dev), buf);
214 		if (!backup_dev)
215 			return -ENOENT;
216 	}
217 
218 	return nbp_backup_change(p, backup_dev);
219 }
220 static BRPORT_ATTR_RAW(backup_port, 0644, show_backup_port, store_backup_port);
221 
222 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
223 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
224 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
225 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
226 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
227 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
228 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
229 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
230 BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
231 BRPORT_ATTR_FLAG(neigh_suppress, BR_NEIGH_SUPPRESS);
232 BRPORT_ATTR_FLAG(isolated, BR_ISOLATED);
233 
234 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
235 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
236 {
237 	return sprintf(buf, "%d\n", p->multicast_router);
238 }
239 
240 static int store_multicast_router(struct net_bridge_port *p,
241 				      unsigned long v)
242 {
243 	return br_multicast_set_port_router(p, v);
244 }
245 static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
246 		   store_multicast_router);
247 
248 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
249 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
250 #endif
251 
252 static const struct brport_attribute *brport_attrs[] = {
253 	&brport_attr_path_cost,
254 	&brport_attr_priority,
255 	&brport_attr_port_id,
256 	&brport_attr_port_no,
257 	&brport_attr_designated_root,
258 	&brport_attr_designated_bridge,
259 	&brport_attr_designated_port,
260 	&brport_attr_designated_cost,
261 	&brport_attr_state,
262 	&brport_attr_change_ack,
263 	&brport_attr_config_pending,
264 	&brport_attr_message_age_timer,
265 	&brport_attr_forward_delay_timer,
266 	&brport_attr_hold_timer,
267 	&brport_attr_flush,
268 	&brport_attr_hairpin_mode,
269 	&brport_attr_bpdu_guard,
270 	&brport_attr_root_block,
271 	&brport_attr_learning,
272 	&brport_attr_unicast_flood,
273 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
274 	&brport_attr_multicast_router,
275 	&brport_attr_multicast_fast_leave,
276 	&brport_attr_multicast_to_unicast,
277 #endif
278 	&brport_attr_proxyarp,
279 	&brport_attr_proxyarp_wifi,
280 	&brport_attr_multicast_flood,
281 	&brport_attr_broadcast_flood,
282 	&brport_attr_group_fwd_mask,
283 	&brport_attr_neigh_suppress,
284 	&brport_attr_isolated,
285 	&brport_attr_backup_port,
286 	NULL
287 };
288 
289 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
290 
291 static ssize_t brport_show(struct kobject *kobj,
292 			   struct attribute *attr, char *buf)
293 {
294 	struct brport_attribute *brport_attr = to_brport_attr(attr);
295 	struct net_bridge_port *p = kobj_to_brport(kobj);
296 
297 	if (!brport_attr->show)
298 		return -EINVAL;
299 
300 	return brport_attr->show(p, buf);
301 }
302 
303 static ssize_t brport_store(struct kobject *kobj,
304 			    struct attribute *attr,
305 			    const char *buf, size_t count)
306 {
307 	struct brport_attribute *brport_attr = to_brport_attr(attr);
308 	struct net_bridge_port *p = kobj_to_brport(kobj);
309 	ssize_t ret = -EINVAL;
310 	unsigned long val;
311 	char *endp;
312 
313 	if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
314 		return -EPERM;
315 
316 	if (!rtnl_trylock())
317 		return restart_syscall();
318 
319 	if (brport_attr->store_raw) {
320 		char *buf_copy;
321 
322 		buf_copy = kstrndup(buf, count, GFP_KERNEL);
323 		if (!buf_copy) {
324 			ret = -ENOMEM;
325 			goto out_unlock;
326 		}
327 		spin_lock_bh(&p->br->lock);
328 		ret = brport_attr->store_raw(p, buf_copy);
329 		spin_unlock_bh(&p->br->lock);
330 		kfree(buf_copy);
331 	} else if (brport_attr->store) {
332 		val = simple_strtoul(buf, &endp, 0);
333 		if (endp == buf)
334 			goto out_unlock;
335 		spin_lock_bh(&p->br->lock);
336 		ret = brport_attr->store(p, val);
337 		spin_unlock_bh(&p->br->lock);
338 	}
339 
340 	if (!ret) {
341 		br_ifinfo_notify(RTM_NEWLINK, NULL, p);
342 		ret = count;
343 	}
344 out_unlock:
345 	rtnl_unlock();
346 
347 	return ret;
348 }
349 
350 const struct sysfs_ops brport_sysfs_ops = {
351 	.show = brport_show,
352 	.store = brport_store,
353 };
354 
355 /*
356  * Add sysfs entries to ethernet device added to a bridge.
357  * Creates a brport subdirectory with bridge attributes.
358  * Puts symlink in bridge's brif subdirectory
359  */
360 int br_sysfs_addif(struct net_bridge_port *p)
361 {
362 	struct net_bridge *br = p->br;
363 	const struct brport_attribute **a;
364 	int err;
365 
366 	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
367 				SYSFS_BRIDGE_PORT_LINK);
368 	if (err)
369 		return err;
370 
371 	for (a = brport_attrs; *a; ++a) {
372 		err = sysfs_create_file(&p->kobj, &((*a)->attr));
373 		if (err)
374 			return err;
375 	}
376 
377 	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
378 	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
379 }
380 
381 /* Rename bridge's brif symlink */
382 int br_sysfs_renameif(struct net_bridge_port *p)
383 {
384 	struct net_bridge *br = p->br;
385 	int err;
386 
387 	/* If a rename fails, the rollback will cause another
388 	 * rename call with the existing name.
389 	 */
390 	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
391 		return 0;
392 
393 	err = sysfs_rename_link(br->ifobj, &p->kobj,
394 				p->sysfs_name, p->dev->name);
395 	if (err)
396 		netdev_notice(br->dev, "unable to rename link %s to %s",
397 			      p->sysfs_name, p->dev->name);
398 	else
399 		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
400 
401 	return err;
402 }
403