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
24struct 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) \
32const 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) \
40const 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) \
48static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
49{ \
50 return sprintf(buf, "%d\n", !!(p->flags & _mask)); \
51} \
52static int store_##_name(struct net_bridge_port *p, unsigned long v) \
53{ \
54 return store_flag(p, v, _mask); \
55} \
56static BRPORT_ATTR(_name, 0644, \
57 show_##_name, store_##_name)
58
59static 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: &extack);
73 if (err) {
74 netdev_err(dev: p->dev, format: "%s\n", extack._msg);
75 return err;
76 }
77
78 p->flags = flags;
79 br_port_flags_change(port: p, mask);
80 }
81 return 0;
82}
83
84static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
85{
86 return sprintf(buf, fmt: "%d\n", p->path_cost);
87}
88
89static BRPORT_ATTR(path_cost, 0644,
90 show_path_cost, br_stp_set_path_cost);
91
92static ssize_t show_priority(struct net_bridge_port *p, char *buf)
93{
94 return sprintf(buf, fmt: "%d\n", p->priority);
95}
96
97static BRPORT_ATTR(priority, 0644,
98 show_priority, br_stp_set_port_priority);
99
100static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
101{
102 return br_show_bridge_id(buf, id: &p->designated_root);
103}
104static BRPORT_ATTR(designated_root, 0444, show_designated_root, NULL);
105
106static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
107{
108 return br_show_bridge_id(buf, id: &p->designated_bridge);
109}
110static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL);
111
112static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
113{
114 return sprintf(buf, fmt: "%d\n", p->designated_port);
115}
116static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL);
117
118static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
119{
120 return sprintf(buf, fmt: "%d\n", p->designated_cost);
121}
122static BRPORT_ATTR(designated_cost, 0444, show_designated_cost, NULL);
123
124static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
125{
126 return sprintf(buf, fmt: "0x%x\n", p->port_id);
127}
128static BRPORT_ATTR(port_id, 0444, show_port_id, NULL);
129
130static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
131{
132 return sprintf(buf, fmt: "0x%x\n", p->port_no);
133}
134
135static BRPORT_ATTR(port_no, 0444, show_port_no, NULL);
136
137static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
138{
139 return sprintf(buf, fmt: "%d\n", p->topology_change_ack);
140}
141static BRPORT_ATTR(change_ack, 0444, show_change_ack, NULL);
142
143static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
144{
145 return sprintf(buf, fmt: "%d\n", p->config_pending);
146}
147static BRPORT_ATTR(config_pending, 0444, show_config_pending, NULL);
148
149static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
150{
151 return sprintf(buf, fmt: "%d\n", p->state);
152}
153static BRPORT_ATTR(state, 0444, show_port_state, NULL);
154
155static ssize_t show_message_age_timer(struct net_bridge_port *p,
156 char *buf)
157{
158 return sprintf(buf, fmt: "%ld\n", br_timer_value(timer: &p->message_age_timer));
159}
160static BRPORT_ATTR(message_age_timer, 0444, show_message_age_timer, NULL);
161
162static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
163 char *buf)
164{
165 return sprintf(buf, fmt: "%ld\n", br_timer_value(timer: &p->forward_delay_timer));
166}
167static BRPORT_ATTR(forward_delay_timer, 0444, show_forward_delay_timer, NULL);
168
169static ssize_t show_hold_timer(struct net_bridge_port *p,
170 char *buf)
171{
172 return sprintf(buf, fmt: "%ld\n", br_timer_value(timer: &p->hold_timer));
173}
174static BRPORT_ATTR(hold_timer, 0444, show_hold_timer, NULL);
175
176static int store_flush(struct net_bridge_port *p, unsigned long v)
177{
178 br_fdb_delete_by_port(br: p->br, p, vid: 0, do_all: 0); // Don't delete local entry
179 return 0;
180}
181static BRPORT_ATTR(flush, 0200, NULL, store_flush);
182
183static ssize_t show_group_fwd_mask(struct net_bridge_port *p, char *buf)
184{
185 return sprintf(buf, fmt: "%#x\n", p->group_fwd_mask);
186}
187
188static 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}
197static BRPORT_ATTR(group_fwd_mask, 0644, show_group_fwd_mask,
198 store_group_fwd_mask);
199
200static 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, fmt: "%s\n", backup_p->dev->name);
209 rcu_read_unlock();
210
211 return ret;
212}
213
214static 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(net: dev_net(dev: p->dev), name: buf);
224 if (!backup_dev)
225 return -ENOENT;
226 }
227
228 return nbp_backup_change(p, backup_dev);
229}
230static BRPORT_ATTR_RAW(backup_port, 0644, show_backup_port, store_backup_port);
231
232BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
233BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
234BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
235BRPORT_ATTR_FLAG(learning, BR_LEARNING);
236BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
237BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
238BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
239BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
240BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
241BRPORT_ATTR_FLAG(neigh_suppress, BR_NEIGH_SUPPRESS);
242BRPORT_ATTR_FLAG(isolated, BR_ISOLATED);
243
244#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
245static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
246{
247 return sprintf(buf, fmt: "%d\n", p->multicast_ctx.multicast_router);
248}
249
250static int store_multicast_router(struct net_bridge_port *p,
251 unsigned long v)
252{
253 return br_multicast_set_port_router(pmctx: &p->multicast_ctx, val: v);
254}
255static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
256 store_multicast_router);
257
258BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
259BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
260#endif
261
262static 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
301static 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
313static 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(ns: dev_net(dev: 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(s: buf, len: count, GFP_KERNEL);
333 if (!buf_copy) {
334 ret = -ENOMEM;
335 goto out_unlock;
336 }
337 spin_lock_bh(lock: &p->br->lock);
338 ret = brport_attr->store_raw(p, buf_copy);
339 spin_unlock_bh(lock: &p->br->lock);
340 kfree(objp: 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(lock: &p->br->lock);
346 ret = brport_attr->store(p, val);
347 spin_unlock_bh(lock: &p->br->lock);
348 }
349
350 if (!ret) {
351 br_ifinfo_notify(RTM_NEWLINK, NULL, port: p);
352 ret = count;
353 }
354out_unlock:
355 rtnl_unlock();
356
357 return ret;
358}
359
360const 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 */
370int 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(kobj: &p->kobj, target: &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(kobj: &p->kobj, attr: &((*a)->attr));
383 if (err)
384 return err;
385 }
386
387 strscpy(p: p->sysfs_name, q: p->dev->name, IFNAMSIZ);
388 return sysfs_create_link(kobj: br->ifobj, target: &p->kobj, name: p->sysfs_name);
389}
390
391/* Rename bridge's brif symlink */
392int 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(kobj: br->ifobj, target: &p->kobj,
404 old_name: p->sysfs_name, new_name: p->dev->name);
405 if (err)
406 netdev_notice(dev: br->dev, format: "unable to rename link %s to %s",
407 p->sysfs_name, p->dev->name);
408 else
409 strscpy(p: p->sysfs_name, q: p->dev->name, IFNAMSIZ);
410
411 return err;
412}
413

source code of linux/net/bridge/br_sysfs_if.c