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         }
  65         return 0;
  66 }
  67
  68 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
  69 {
  70         return sprintf(buf, "%d\n", p->path_cost);
  71 }
  72
  73 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
  74                    show_path_cost, br_stp_set_path_cost);
  75
  76 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  77 {
  78         return sprintf(buf, "%d\n", p->priority);
  79 }
  80
  81 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
  82                          show_priority, br_stp_set_port_priority);
  83
  84 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  85 {
  86         return br_show_bridge_id(buf, &p->designated_root);
  87 }
  88 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
  89
  90 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
  91 {
  92         return br_show_bridge_id(buf, &p->designated_bridge);
  93 }
  94 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
  95
  96 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
  97 {
  98         return sprintf(buf, "%d\n", p->designated_port);
  99 }
 100 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
 101
 102 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
 103 {
 104         return sprintf(buf, "%d\n", p->designated_cost);
 105 }
 106 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
 107
 108 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
 109 {
 110         return sprintf(buf, "0x%x\n", p->port_id);
 111 }
 112 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
 113
 114 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
 115 {
 116         return sprintf(buf, "0x%x\n", p->port_no);
 117 }
 118
 119 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
 120
 121 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 122 {
 123         return sprintf(buf, "%d\n", p->topology_change_ack);
 124 }
 125 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
 126
 127 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 128 {
 129         return sprintf(buf, "%d\n", p->config_pending);
 130 }
 131 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
 132
 133 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 134 {
 135         return sprintf(buf, "%d\n", p->state);
 136 }
 137 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
 138
 139 static ssize_t show_message_age_timer(struct net_bridge_port *p,
 140                                             char *buf)
 141 {
 142         return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
 143 }
 144 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
 145
 146 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
 147                                             char *buf)
 148 {
 149         return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
 150 }
 151 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
 152
 153 static ssize_t show_hold_timer(struct net_bridge_port *p,
 154                                             char *buf)
 155 {
 156         return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
 157 }
 158 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 159
 160 static int store_flush(struct net_bridge_port *p, unsigned long v)
 161 {
 162         br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
 163         return 0;
 164 }
 165 static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
 166
 167 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
 168 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
 169 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
 170 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 171 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 172 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
 173 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
 174 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
 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         return brport_attr->show(p, buf);
 233 }
 234
 235 static ssize_t brport_store(struct kobject *kobj,
 236                             struct attribute *attr,
 237                             const char *buf, size_t count)
 238 {
 239         struct brport_attribute *brport_attr = to_brport_attr(attr);
 240         struct net_bridge_port *p = to_brport(kobj);
 241         ssize_t ret = -EINVAL;
 242         char *endp;
 243         unsigned long val;
 244
 245         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 246                 return -EPERM;
 247
 248         val = simple_strtoul(buf, &endp, 0);
 249         if (endp != buf) {
 250                 if (!rtnl_trylock())
 251                         return restart_syscall();
 252                 if (p->dev && p->br && brport_attr->store) {
 253                         spin_lock_bh(&p->br->lock);
 254                         ret = brport_attr->store(p, val);
 255                         spin_unlock_bh(&p->br->lock);
 256                         if (!ret) {
 257                                 br_ifinfo_notify(RTM_NEWLINK, p);
 258                                 ret = count;
 259                         }
 260                 }
 261                 rtnl_unlock();
 262         }
 263         return ret;
 264 }
 265
 266 const struct sysfs_ops brport_sysfs_ops = {
 267         .show = brport_show,
 268         .store = brport_store,
 269 };
 270
 271 /*
 272  * Add sysfs entries to ethernet device added to a bridge.
 273  * Creates a brport subdirectory with bridge attributes.
 274  * Puts symlink in bridge's brif subdirectory
 275  */
 276 int br_sysfs_addif(struct net_bridge_port *p)
 277 {
 278         struct net_bridge *br = p->br;
 279         const struct brport_attribute **a;
 280         int err;
 281
 282         err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
 283                                 SYSFS_BRIDGE_PORT_LINK);
 284         if (err)
 285                 return err;
 286
 287         for (a = brport_attrs; *a; ++a) {
 288                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 289                 if (err)
 290                         return err;
 291         }
 292
 293         strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 294         return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
 295 }
 296
 297 /* Rename bridge's brif symlink */
 298 int br_sysfs_renameif(struct net_bridge_port *p)
 299 {
 300         struct net_bridge *br = p->br;
 301         int err;
 302
 303         /* If a rename fails, the rollback will cause another
 304          * rename call with the existing name.
 305          */
 306         if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
 307                 return 0;
 308
 309         err = sysfs_rename_link(br->ifobj, &p->kobj,
 310                                 p->sysfs_name, p->dev->name);
 311         if (err)
 312                 netdev_notice(br->dev, "unable to rename link %s to %s",
 313                               p->sysfs_name, p->dev->name);
 314         else
 315                 strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 316
 317         return err;
 318 }