net/bridge/br_sysfs_if.c

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