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