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
  21 #include "br_private.h"
  22
  23 struct brport_attribute {
  24         struct attribute        attr;
  25         ssize_t (*show)(struct net_bridge_port *, char *);
  26         int (*store)(struct net_bridge_port *, unsigned long);
  27 };
  28
  29 #define BRPORT_ATTR(_name, _mode, _show, _store)                \
  30 const struct brport_attribute brport_attr_##_name = {           \
  31         .attr = {.name = __stringify(_name),                    \
  32                  .mode = _mode },                               \
  33         .show   = _show,                                        \
  34         .store  = _store,                                       \
  35 };
  36
  37 #define BRPORT_ATTR_FLAG(_name, _mask)                          \
  38 static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
  39 {                                                               \
  40         return sprintf(buf, "%d\n", !!(p->flags & _mask));      \
  41 }                                                               \
  42 static int store_##_name(struct net_bridge_port *p, unsigned long v) \
  43 {                                                               \
  44         return store_flag(p, v, _mask);                         \
  45 }                                                               \
  46 static BRPORT_ATTR(_name, S_IRUGO | S_IWUSR,                    \
  47                    show_##_name, store_##_name)
  48
  49 static int store_flag(struct net_bridge_port *p, unsigned long v,
  50                       unsigned long mask)
  51 {
  52         unsigned long flags;
  53
  54         flags = p->flags;
  55
  56         if (v)
  57                 flags |= mask;
  58         else
  59                 flags &= ~mask;
  60
  61         if (flags != p->flags) {
  62                 p->flags = flags;
  63                 br_port_flags_change(p, mask);
  64                 br_ifinfo_notify(RTM_NEWLINK, p);
  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, S_IRUGO | S_IWUSR,
  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, S_IRUGO | S_IWUSR,
  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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IRUGO, 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, S_IWUSR, NULL, store_flush);
 167
 168 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
 169 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
 170 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
 171 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 172 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 173 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
 174 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
 175
 176 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 177 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 178 {
 179         return sprintf(buf, "%d\n", p->multicast_router);
 180 }
 181
 182 static int store_multicast_router(struct net_bridge_port *p,
 183                                       unsigned long v)
 184 {
 185         return br_multicast_set_port_router(p, v);
 186 }
 187 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
 188                    store_multicast_router);
 189
 190 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 191 #endif
 192
 193 static const struct brport_attribute *brport_attrs[] = {
 194         &brport_attr_path_cost,
 195         &brport_attr_priority,
 196         &brport_attr_port_id,
 197         &brport_attr_port_no,
 198         &brport_attr_designated_root,
 199         &brport_attr_designated_bridge,
 200         &brport_attr_designated_port,
 201         &brport_attr_designated_cost,
 202         &brport_attr_state,
 203         &brport_attr_change_ack,
 204         &brport_attr_config_pending,
 205         &brport_attr_message_age_timer,
 206         &brport_attr_forward_delay_timer,
 207         &brport_attr_hold_timer,
 208         &brport_attr_flush,
 209         &brport_attr_hairpin_mode,
 210         &brport_attr_bpdu_guard,
 211         &brport_attr_root_block,
 212         &brport_attr_learning,
 213         &brport_attr_unicast_flood,
 214 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 215         &brport_attr_multicast_router,
 216         &brport_attr_multicast_fast_leave,
 217 #endif
 218         &brport_attr_proxyarp,
 219         &brport_attr_proxyarp_wifi,
 220         NULL
 221 };
 222
 223 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 224 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 225
 226 static ssize_t brport_show(struct kobject *kobj,
 227                            struct attribute *attr, char *buf)
 228 {
 229         struct brport_attribute *brport_attr = to_brport_attr(attr);
 230         struct net_bridge_port *p = to_brport(kobj);
 231
 232         if (!brport_attr->show)
 233                 return -EINVAL;
 234
 235         return brport_attr->show(p, buf);
 236 }
 237
 238 static ssize_t brport_store(struct kobject *kobj,
 239                             struct attribute *attr,
 240                             const char *buf, size_t count)
 241 {
 242         struct brport_attribute *brport_attr = to_brport_attr(attr);
 243         struct net_bridge_port *p = to_brport(kobj);
 244         ssize_t ret = -EINVAL;
 245         char *endp;
 246         unsigned long val;
 247
 248         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 249                 return -EPERM;
 250
 251         val = simple_strtoul(buf, &endp, 0);
 252         if (endp != buf) {
 253                 if (!rtnl_trylock())
 254                         return restart_syscall();
 255                 if (p->dev && p->br && brport_attr->store) {
 256                         spin_lock_bh(&p->br->lock);
 257                         ret = brport_attr->store(p, val);
 258                         spin_unlock_bh(&p->br->lock);
 259                         if (ret == 0)
 260                                 ret = count;
 261                 }
 262                 rtnl_unlock();
 263         }
 264         return ret;
 265 }
 266
 267 const struct sysfs_ops brport_sysfs_ops = {
 268         .show = brport_show,
 269         .store = brport_store,
 270 };
 271
 272 /*
 273  * Add sysfs entries to ethernet device added to a bridge.
 274  * Creates a brport subdirectory with bridge attributes.
 275  * Puts symlink in bridge's brif subdirectory
 276  */
 277 int br_sysfs_addif(struct net_bridge_port *p)
 278 {
 279         struct net_bridge *br = p->br;
 280         const struct brport_attribute **a;
 281         int err;
 282
 283         err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
 284                                 SYSFS_BRIDGE_PORT_LINK);
 285         if (err)
 286                 return err;
 287
 288         for (a = brport_attrs; *a; ++a) {
 289                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 290                 if (err)
 291                         return err;
 292         }
 293
 294         strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 295         return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
 296 }
 297
 298 /* Rename bridge's brif symlink */
 299 int br_sysfs_renameif(struct net_bridge_port *p)
 300 {
 301         struct net_bridge *br = p->br;
 302         int err;
 303
 304         /* If a rename fails, the rollback will cause another
 305          * rename call with the existing name.
 306          */
 307         if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
 308                 return 0;
 309
 310         err = sysfs_rename_link(br->ifobj, &p->kobj,
 311                                 p->sysfs_name, p->dev->name);
 312         if (err)
 313                 netdev_notice(br->dev, "unable to rename link %s to %s",
 314                               p->sysfs_name, p->dev->name);
 315         else
 316                 strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 317
 318         return err;
 319 }