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); // 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
 175 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 176 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 177 {
 178         return sprintf(buf, "%d\n", p->multicast_router);
 179 }
 180
 181 static int store_multicast_router(struct net_bridge_port *p,
 182                                       unsigned long v)
 183 {
 184         return br_multicast_set_port_router(p, v);
 185 }
 186 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
 187                    store_multicast_router);
 188
 189 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 190 #endif
 191
 192 static const struct brport_attribute *brport_attrs[] = {
 193         &brport_attr_path_cost,
 194         &brport_attr_priority,
 195         &brport_attr_port_id,
 196         &brport_attr_port_no,
 197         &brport_attr_designated_root,
 198         &brport_attr_designated_bridge,
 199         &brport_attr_designated_port,
 200         &brport_attr_designated_cost,
 201         &brport_attr_state,
 202         &brport_attr_change_ack,
 203         &brport_attr_config_pending,
 204         &brport_attr_message_age_timer,
 205         &brport_attr_forward_delay_timer,
 206         &brport_attr_hold_timer,
 207         &brport_attr_flush,
 208         &brport_attr_hairpin_mode,
 209         &brport_attr_bpdu_guard,
 210         &brport_attr_root_block,
 211         &brport_attr_learning,
 212         &brport_attr_unicast_flood,
 213 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 214         &brport_attr_multicast_router,
 215         &brport_attr_multicast_fast_leave,
 216 #endif
 217         &brport_attr_proxyarp,
 218         NULL
 219 };
 220
 221 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 222 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 223
 224 static ssize_t brport_show(struct kobject *kobj,
 225                            struct attribute *attr, char *buf)
 226 {
 227         struct brport_attribute *brport_attr = to_brport_attr(attr);
 228         struct net_bridge_port *p = to_brport(kobj);
 229
 230         return brport_attr->show(p, buf);
 231 }
 232
 233 static ssize_t brport_store(struct kobject *kobj,
 234                             struct attribute *attr,
 235                             const char *buf, size_t count)
 236 {
 237         struct brport_attribute *brport_attr = to_brport_attr(attr);
 238         struct net_bridge_port *p = to_brport(kobj);
 239         ssize_t ret = -EINVAL;
 240         char *endp;
 241         unsigned long val;
 242
 243         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 244                 return -EPERM;
 245
 246         val = simple_strtoul(buf, &endp, 0);
 247         if (endp != buf) {
 248                 if (!rtnl_trylock())
 249                         return restart_syscall();
 250                 if (p->dev && p->br && brport_attr->store) {
 251                         spin_lock_bh(&p->br->lock);
 252                         ret = brport_attr->store(p, val);
 253                         spin_unlock_bh(&p->br->lock);
 254                         if (ret == 0)
 255                                 ret = count;
 256                 }
 257                 rtnl_unlock();
 258         }
 259         return ret;
 260 }
 261
 262 const struct sysfs_ops brport_sysfs_ops = {
 263         .show = brport_show,
 264         .store = brport_store,
 265 };
 266
 267 /*
 268  * Add sysfs entries to ethernet device added to a bridge.
 269  * Creates a brport subdirectory with bridge attributes.
 270  * Puts symlink in bridge's brif subdirectory
 271  */
 272 int br_sysfs_addif(struct net_bridge_port *p)
 273 {
 274         struct net_bridge *br = p->br;
 275         const struct brport_attribute **a;
 276         int err;
 277
 278         err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
 279                                 SYSFS_BRIDGE_PORT_LINK);
 280         if (err)
 281                 return err;
 282
 283         for (a = brport_attrs; *a; ++a) {
 284                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 285                 if (err)
 286                         return err;
 287         }
 288
 289         strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 290         return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
 291 }
 292
 293 /* Rename bridge's brif symlink */
 294 int br_sysfs_renameif(struct net_bridge_port *p)
 295 {
 296         struct net_bridge *br = p->br;
 297         int err;
 298
 299         /* If a rename fails, the rollback will cause another
 300          * rename call with the existing name.
 301          */
 302         if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
 303                 return 0;
 304
 305         err = sysfs_rename_link(br->ifobj, &p->kobj,
 306                                 p->sysfs_name, p->dev->name);
 307         if (err)
 308                 netdev_notice(br->dev, "unable to rename link %s to %s",
 309                               p->sysfs_name, p->dev->name);
 310         else
 311                 strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 312
 313         return err;
 314 }