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
store_flag(struct net_bridge_port * p,unsigned long v,unsigned long mask)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
show_path_cost(struct net_bridge_port * p,char * buf)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
show_priority(struct net_bridge_port * p,char * buf)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
show_designated_root(struct net_bridge_port * p,char * buf)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
show_designated_bridge(struct net_bridge_port * p,char * buf)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
show_designated_port(struct net_bridge_port * p,char * buf)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
show_designated_cost(struct net_bridge_port * p,char * buf)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
show_port_id(struct net_bridge_port * p,char * buf)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
show_port_no(struct net_bridge_port * p,char * buf)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
show_change_ack(struct net_bridge_port * p,char * buf)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
show_config_pending(struct net_bridge_port * p,char * buf)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
show_port_state(struct net_bridge_port * p,char * buf)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
show_message_age_timer(struct net_bridge_port * p,char * buf)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
show_forward_delay_timer(struct net_bridge_port * p,char * buf)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
show_hold_timer(struct net_bridge_port * p,char * buf)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
store_flush(struct net_bridge_port * p,unsigned long v)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
show_group_fwd_mask(struct net_bridge_port * p,char * buf)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
store_group_fwd_mask(struct net_bridge_port * p,unsigned long v)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
show_backup_port(struct net_bridge_port * p,char * buf)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
store_backup_port(struct net_bridge_port * p,char * buf)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
show_multicast_router(struct net_bridge_port * p,char * buf)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
store_multicast_router(struct net_bridge_port * p,unsigned long v)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
brport_show(struct kobject * kobj,struct attribute * attr,char * buf)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
brport_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t count)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 */
br_sysfs_addif(struct net_bridge_port * p)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 */
br_sysfs_renameif(struct net_bridge_port * p)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