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 = p->flags;
  63         int err;
  64
  65         if (v)
  66                 flags |= mask;
  67         else
  68                 flags &= ~mask;
  69
  70         if (flags != p->flags) {
  71                 err = br_switchdev_set_port_flag(p, flags, mask);
  72                 if (err)
  73                         return err;
  74
  75                 p->flags = flags;
  76                 br_port_flags_change(p, mask);
  77         }
  78         return 0;
  79 }
  80
  81 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
  82 {
  83         return sprintf(buf, "%d\n", p->path_cost);
  84 }
  85
  86 static BRPORT_ATTR(path_cost, 0644,
  87                    show_path_cost, br_stp_set_path_cost);
  88
  89 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  90 {
  91         return sprintf(buf, "%d\n", p->priority);
  92 }
  93
  94 static BRPORT_ATTR(priority, 0644,
  95                          show_priority, br_stp_set_port_priority);
  96
  97 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  98 {
  99         return br_show_bridge_id(buf, &p->designated_root);
 100 }
 101 static BRPORT_ATTR(designated_root, 0444, show_designated_root, NULL);
 102
 103 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
 104 {
 105         return br_show_bridge_id(buf, &p->designated_bridge);
 106 }
 107 static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL);
 108
 109 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
 110 {
 111         return sprintf(buf, "%d\n", p->designated_port);
 112 }
 113 static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL);
 114
 115 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
 116 {
 117         return sprintf(buf, "%d\n", p->designated_cost);
 118 }
 119 static BRPORT_ATTR(designated_cost, 0444, show_designated_cost, NULL);
 120
 121 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
 122 {
 123         return sprintf(buf, "0x%x\n", p->port_id);
 124 }
 125 static BRPORT_ATTR(port_id, 0444, show_port_id, NULL);
 126
 127 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
 128 {
 129         return sprintf(buf, "0x%x\n", p->port_no);
 130 }
 131
 132 static BRPORT_ATTR(port_no, 0444, show_port_no, NULL);
 133
 134 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 135 {
 136         return sprintf(buf, "%d\n", p->topology_change_ack);
 137 }
 138 static BRPORT_ATTR(change_ack, 0444, show_change_ack, NULL);
 139
 140 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 141 {
 142         return sprintf(buf, "%d\n", p->config_pending);
 143 }
 144 static BRPORT_ATTR(config_pending, 0444, show_config_pending, NULL);
 145
 146 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 147 {
 148         return sprintf(buf, "%d\n", p->state);
 149 }
 150 static BRPORT_ATTR(state, 0444, show_port_state, NULL);
 151
 152 static ssize_t show_message_age_timer(struct net_bridge_port *p,
 153                                             char *buf)
 154 {
 155         return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
 156 }
 157 static BRPORT_ATTR(message_age_timer, 0444, show_message_age_timer, NULL);
 158
 159 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
 160                                             char *buf)
 161 {
 162         return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
 163 }
 164 static BRPORT_ATTR(forward_delay_timer, 0444, show_forward_delay_timer, NULL);
 165
 166 static ssize_t show_hold_timer(struct net_bridge_port *p,
 167                                             char *buf)
 168 {
 169         return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
 170 }
 171 static BRPORT_ATTR(hold_timer, 0444, show_hold_timer, NULL);
 172
 173 static int store_flush(struct net_bridge_port *p, unsigned long v)
 174 {
 175         br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
 176         return 0;
 177 }
 178 static BRPORT_ATTR(flush, 0200, NULL, store_flush);
 179
 180 static ssize_t show_group_fwd_mask(struct net_bridge_port *p, char *buf)
 181 {
 182         return sprintf(buf, "%#x\n", p->group_fwd_mask);
 183 }
 184
 185 static int store_group_fwd_mask(struct net_bridge_port *p,
 186                                 unsigned long v)
 187 {
 188         if (v & BR_GROUPFWD_MACPAUSE)
 189                 return -EINVAL;
 190         p->group_fwd_mask = v;
 191
 192         return 0;
 193 }
 194 static BRPORT_ATTR(group_fwd_mask, 0644, show_group_fwd_mask,
 195                    store_group_fwd_mask);
 196
 197 static ssize_t show_backup_port(struct net_bridge_port *p, char *buf)
 198 {
 199         struct net_bridge_port *backup_p;
 200         int ret = 0;
 201
 202         rcu_read_lock();
 203         backup_p = rcu_dereference(p->backup_port);
 204         if (backup_p)
 205                 ret = sprintf(buf, "%s\n", backup_p->dev->name);
 206         rcu_read_unlock();
 207
 208         return ret;
 209 }
 210
 211 static int store_backup_port(struct net_bridge_port *p, char *buf)
 212 {
 213         struct net_device *backup_dev = NULL;
 214         char *nl = strchr(buf, '\n');
 215
 216         if (nl)
 217                 *nl = '\0';
 218
 219         if (strlen(buf) > 0) {
 220                 backup_dev = __dev_get_by_name(dev_net(p->dev), buf);
 221                 if (!backup_dev)
 222                         return -ENOENT;
 223         }
 224
 225         return nbp_backup_change(p, backup_dev);
 226 }
 227 static BRPORT_ATTR_RAW(backup_port, 0644, show_backup_port, store_backup_port);
 228
 229 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
 230 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
 231 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
 232 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 233 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 234 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
 235 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
 236 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
 237 BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
 238 BRPORT_ATTR_FLAG(neigh_suppress, BR_NEIGH_SUPPRESS);
 239 BRPORT_ATTR_FLAG(isolated, BR_ISOLATED);
 240
 241 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 242 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 243 {
 244         return sprintf(buf, "%d\n", p->multicast_router);
 245 }
 246
 247 static int store_multicast_router(struct net_bridge_port *p,
 248                                       unsigned long v)
 249 {
 250         return br_multicast_set_port_router(p, v);
 251 }
 252 static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
 253                    store_multicast_router);
 254
 255 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 256 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
 257 #endif
 258
 259 static const struct brport_attribute *brport_attrs[] = {
 260         &brport_attr_path_cost,
 261         &brport_attr_priority,
 262         &brport_attr_port_id,
 263         &brport_attr_port_no,
 264         &brport_attr_designated_root,
 265         &brport_attr_designated_bridge,
 266         &brport_attr_designated_port,
 267         &brport_attr_designated_cost,
 268         &brport_attr_state,
 269         &brport_attr_change_ack,
 270         &brport_attr_config_pending,
 271         &brport_attr_message_age_timer,
 272         &brport_attr_forward_delay_timer,
 273         &brport_attr_hold_timer,
 274         &brport_attr_flush,
 275         &brport_attr_hairpin_mode,
 276         &brport_attr_bpdu_guard,
 277         &brport_attr_root_block,
 278         &brport_attr_learning,
 279         &brport_attr_unicast_flood,
 280 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 281         &brport_attr_multicast_router,
 282         &brport_attr_multicast_fast_leave,
 283         &brport_attr_multicast_to_unicast,
 284 #endif
 285         &brport_attr_proxyarp,
 286         &brport_attr_proxyarp_wifi,
 287         &brport_attr_multicast_flood,
 288         &brport_attr_broadcast_flood,
 289         &brport_attr_group_fwd_mask,
 290         &brport_attr_neigh_suppress,
 291         &brport_attr_isolated,
 292         &brport_attr_backup_port,
 293         NULL
 294 };
 295
 296 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 297
 298 static ssize_t brport_show(struct kobject *kobj,
 299                            struct attribute *attr, char *buf)
 300 {
 301         struct brport_attribute *brport_attr = to_brport_attr(attr);
 302         struct net_bridge_port *p = kobj_to_brport(kobj);
 303
 304         if (!brport_attr->show)
 305                 return -EINVAL;
 306
 307         return brport_attr->show(p, buf);
 308 }
 309
 310 static ssize_t brport_store(struct kobject *kobj,
 311                             struct attribute *attr,
 312                             const char *buf, size_t count)
 313 {
 314         struct brport_attribute *brport_attr = to_brport_attr(attr);
 315         struct net_bridge_port *p = kobj_to_brport(kobj);
 316         ssize_t ret = -EINVAL;
 317         unsigned long val;
 318         char *endp;
 319
 320         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 321                 return -EPERM;
 322
 323         if (!rtnl_trylock())
 324                 return restart_syscall();
 325
 326         if (!p->dev || !p->br)
 327                 goto out_unlock;
 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 }