xref: /openbmc/linux/net/bridge/br_sysfs_if.c (revision d9fd5a71)
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 /* IMPORTANT: new bridge port options must be added with netlink support only
21  *            please do not add new sysfs entries
22  */
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 	int (*store_raw)(struct net_bridge_port *, char *);
29 };
30 
31 #define BRPORT_ATTR_RAW(_name, _mode, _show, _store)			\
32 const struct brport_attribute brport_attr_##_name = {			\
33 	.attr		= {.name = __stringify(_name),			\
34 			   .mode = _mode },				\
35 	.show		= _show,					\
36 	.store_raw	= _store,					\
37 };
38 
39 #define BRPORT_ATTR(_name, _mode, _show, _store)		\
40 const struct brport_attribute brport_attr_##_name = { 	        \
41 	.attr = {.name = __stringify(_name), 			\
42 		 .mode = _mode },				\
43 	.show	= _show,					\
44 	.store	= _store,					\
45 };
46 
47 #define BRPORT_ATTR_FLAG(_name, _mask)				\
48 static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
49 {								\
50 	return sprintf(buf, "%d\n", !!(p->flags & _mask));	\
51 }								\
52 static int store_##_name(struct net_bridge_port *p, unsigned long v) \
53 {								\
54 	return store_flag(p, v, _mask);				\
55 }								\
56 static BRPORT_ATTR(_name, 0644,					\
57 		   show_##_name, store_##_name)
58 
59 static int store_flag(struct net_bridge_port *p, unsigned long v,
60 		      unsigned long mask)
61 {
62 	struct netlink_ext_ack extack = {0};
63 	unsigned long flags = p->flags;
64 	int err;
65 
66 	if (v)
67 		flags |= mask;
68 	else
69 		flags &= ~mask;
70 
71 	if (flags != p->flags) {
72 		err = br_switchdev_set_port_flag(p, flags, mask, &extack);
73 		if (err) {
74 			netdev_err(p->dev, "%s\n", extack._msg);
75 			return err;
76 		}
77 
78 		p->flags = flags;
79 		br_port_flags_change(p, mask);
80 	}
81 	return 0;
82 }
83 
84 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
85 {
86 	return sprintf(buf, "%d\n", p->path_cost);
87 }
88 
89 static BRPORT_ATTR(path_cost, 0644,
90 		   show_path_cost, br_stp_set_path_cost);
91 
92 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
93 {
94 	return sprintf(buf, "%d\n", p->priority);
95 }
96 
97 static BRPORT_ATTR(priority, 0644,
98 			 show_priority, br_stp_set_port_priority);
99 
100 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
101 {
102 	return br_show_bridge_id(buf, &p->designated_root);
103 }
104 static BRPORT_ATTR(designated_root, 0444, show_designated_root, NULL);
105 
106 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
107 {
108 	return br_show_bridge_id(buf, &p->designated_bridge);
109 }
110 static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL);
111 
112 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
113 {
114 	return sprintf(buf, "%d\n", p->designated_port);
115 }
116 static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL);
117 
118 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
119 {
120 	return sprintf(buf, "%d\n", p->designated_cost);
121 }
122 static BRPORT_ATTR(designated_cost, 0444, show_designated_cost, NULL);
123 
124 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
125 {
126 	return sprintf(buf, "0x%x\n", p->port_id);
127 }
128 static BRPORT_ATTR(port_id, 0444, show_port_id, NULL);
129 
130 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
131 {
132 	return sprintf(buf, "0x%x\n", p->port_no);
133 }
134 
135 static BRPORT_ATTR(port_no, 0444, show_port_no, NULL);
136 
137 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
138 {
139 	return sprintf(buf, "%d\n", p->topology_change_ack);
140 }
141 static BRPORT_ATTR(change_ack, 0444, show_change_ack, NULL);
142 
143 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
144 {
145 	return sprintf(buf, "%d\n", p->config_pending);
146 }
147 static BRPORT_ATTR(config_pending, 0444, show_config_pending, NULL);
148 
149 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
150 {
151 	return sprintf(buf, "%d\n", p->state);
152 }
153 static BRPORT_ATTR(state, 0444, show_port_state, NULL);
154 
155 static ssize_t show_message_age_timer(struct net_bridge_port *p,
156 					    char *buf)
157 {
158 	return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
159 }
160 static BRPORT_ATTR(message_age_timer, 0444, show_message_age_timer, NULL);
161 
162 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
163 					    char *buf)
164 {
165 	return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
166 }
167 static BRPORT_ATTR(forward_delay_timer, 0444, show_forward_delay_timer, NULL);
168 
169 static ssize_t show_hold_timer(struct net_bridge_port *p,
170 					    char *buf)
171 {
172 	return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
173 }
174 static BRPORT_ATTR(hold_timer, 0444, show_hold_timer, NULL);
175 
176 static int store_flush(struct net_bridge_port *p, unsigned long v)
177 {
178 	br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
179 	return 0;
180 }
181 static BRPORT_ATTR(flush, 0200, NULL, store_flush);
182 
183 static ssize_t show_group_fwd_mask(struct net_bridge_port *p, char *buf)
184 {
185 	return sprintf(buf, "%#x\n", p->group_fwd_mask);
186 }
187 
188 static int store_group_fwd_mask(struct net_bridge_port *p,
189 				unsigned long v)
190 {
191 	if (v & BR_GROUPFWD_MACPAUSE)
192 		return -EINVAL;
193 	p->group_fwd_mask = v;
194 
195 	return 0;
196 }
197 static BRPORT_ATTR(group_fwd_mask, 0644, show_group_fwd_mask,
198 		   store_group_fwd_mask);
199 
200 static ssize_t show_backup_port(struct net_bridge_port *p, char *buf)
201 {
202 	struct net_bridge_port *backup_p;
203 	int ret = 0;
204 
205 	rcu_read_lock();
206 	backup_p = rcu_dereference(p->backup_port);
207 	if (backup_p)
208 		ret = sprintf(buf, "%s\n", backup_p->dev->name);
209 	rcu_read_unlock();
210 
211 	return ret;
212 }
213 
214 static int store_backup_port(struct net_bridge_port *p, char *buf)
215 {
216 	struct net_device *backup_dev = NULL;
217 	char *nl = strchr(buf, '\n');
218 
219 	if (nl)
220 		*nl = '\0';
221 
222 	if (strlen(buf) > 0) {
223 		backup_dev = __dev_get_by_name(dev_net(p->dev), buf);
224 		if (!backup_dev)
225 			return -ENOENT;
226 	}
227 
228 	return nbp_backup_change(p, backup_dev);
229 }
230 static BRPORT_ATTR_RAW(backup_port, 0644, show_backup_port, store_backup_port);
231 
232 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
233 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
234 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
235 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
236 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
237 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
238 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
239 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
240 BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
241 BRPORT_ATTR_FLAG(neigh_suppress, BR_NEIGH_SUPPRESS);
242 BRPORT_ATTR_FLAG(isolated, BR_ISOLATED);
243 
244 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
245 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
246 {
247 	return sprintf(buf, "%d\n", p->multicast_router);
248 }
249 
250 static int store_multicast_router(struct net_bridge_port *p,
251 				      unsigned long v)
252 {
253 	return br_multicast_set_port_router(p, v);
254 }
255 static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
256 		   store_multicast_router);
257 
258 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
259 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
260 #endif
261 
262 static const struct brport_attribute *brport_attrs[] = {
263 	&brport_attr_path_cost,
264 	&brport_attr_priority,
265 	&brport_attr_port_id,
266 	&brport_attr_port_no,
267 	&brport_attr_designated_root,
268 	&brport_attr_designated_bridge,
269 	&brport_attr_designated_port,
270 	&brport_attr_designated_cost,
271 	&brport_attr_state,
272 	&brport_attr_change_ack,
273 	&brport_attr_config_pending,
274 	&brport_attr_message_age_timer,
275 	&brport_attr_forward_delay_timer,
276 	&brport_attr_hold_timer,
277 	&brport_attr_flush,
278 	&brport_attr_hairpin_mode,
279 	&brport_attr_bpdu_guard,
280 	&brport_attr_root_block,
281 	&brport_attr_learning,
282 	&brport_attr_unicast_flood,
283 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
284 	&brport_attr_multicast_router,
285 	&brport_attr_multicast_fast_leave,
286 	&brport_attr_multicast_to_unicast,
287 #endif
288 	&brport_attr_proxyarp,
289 	&brport_attr_proxyarp_wifi,
290 	&brport_attr_multicast_flood,
291 	&brport_attr_broadcast_flood,
292 	&brport_attr_group_fwd_mask,
293 	&brport_attr_neigh_suppress,
294 	&brport_attr_isolated,
295 	&brport_attr_backup_port,
296 	NULL
297 };
298 
299 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
300 
301 static ssize_t brport_show(struct kobject *kobj,
302 			   struct attribute *attr, char *buf)
303 {
304 	struct brport_attribute *brport_attr = to_brport_attr(attr);
305 	struct net_bridge_port *p = kobj_to_brport(kobj);
306 
307 	if (!brport_attr->show)
308 		return -EINVAL;
309 
310 	return brport_attr->show(p, buf);
311 }
312 
313 static ssize_t brport_store(struct kobject *kobj,
314 			    struct attribute *attr,
315 			    const char *buf, size_t count)
316 {
317 	struct brport_attribute *brport_attr = to_brport_attr(attr);
318 	struct net_bridge_port *p = kobj_to_brport(kobj);
319 	ssize_t ret = -EINVAL;
320 	unsigned long val;
321 	char *endp;
322 
323 	if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
324 		return -EPERM;
325 
326 	if (!rtnl_trylock())
327 		return restart_syscall();
328 
329 	if (brport_attr->store_raw) {
330 		char *buf_copy;
331 
332 		buf_copy = kstrndup(buf, count, GFP_KERNEL);
333 		if (!buf_copy) {
334 			ret = -ENOMEM;
335 			goto out_unlock;
336 		}
337 		spin_lock_bh(&p->br->lock);
338 		ret = brport_attr->store_raw(p, buf_copy);
339 		spin_unlock_bh(&p->br->lock);
340 		kfree(buf_copy);
341 	} else if (brport_attr->store) {
342 		val = simple_strtoul(buf, &endp, 0);
343 		if (endp == buf)
344 			goto out_unlock;
345 		spin_lock_bh(&p->br->lock);
346 		ret = brport_attr->store(p, val);
347 		spin_unlock_bh(&p->br->lock);
348 	}
349 
350 	if (!ret) {
351 		br_ifinfo_notify(RTM_NEWLINK, NULL, p);
352 		ret = count;
353 	}
354 out_unlock:
355 	rtnl_unlock();
356 
357 	return ret;
358 }
359 
360 const struct sysfs_ops brport_sysfs_ops = {
361 	.show = brport_show,
362 	.store = brport_store,
363 };
364 
365 /*
366  * Add sysfs entries to ethernet device added to a bridge.
367  * Creates a brport subdirectory with bridge attributes.
368  * Puts symlink in bridge's brif subdirectory
369  */
370 int br_sysfs_addif(struct net_bridge_port *p)
371 {
372 	struct net_bridge *br = p->br;
373 	const struct brport_attribute **a;
374 	int err;
375 
376 	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
377 				SYSFS_BRIDGE_PORT_LINK);
378 	if (err)
379 		return err;
380 
381 	for (a = brport_attrs; *a; ++a) {
382 		err = sysfs_create_file(&p->kobj, &((*a)->attr));
383 		if (err)
384 			return err;
385 	}
386 
387 	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
388 	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
389 }
390 
391 /* Rename bridge's brif symlink */
392 int br_sysfs_renameif(struct net_bridge_port *p)
393 {
394 	struct net_bridge *br = p->br;
395 	int err;
396 
397 	/* If a rename fails, the rollback will cause another
398 	 * rename call with the existing name.
399 	 */
400 	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
401 		return 0;
402 
403 	err = sysfs_rename_link(br->ifobj, &p->kobj,
404 				p->sysfs_name, p->dev->name);
405 	if (err)
406 		netdev_notice(br->dev, "unable to rename link %s to %s",
407 			      p->sysfs_name, p->dev->name);
408 	else
409 		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
410 
411 	return err;
412 }
413