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, S_IRUGO | S_IWUSR,                    \
  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, 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 BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
 176 BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
 177
 178 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 179 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 180 {
 181         return sprintf(buf, "%d\n", p->multicast_router);
 182 }
 183
 184 static int store_multicast_router(struct net_bridge_port *p,
 185                                       unsigned long v)
 186 {
 187         return br_multicast_set_port_router(p, v);
 188 }
 189 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
 190                    store_multicast_router);
 191
 192 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 193 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
 194 #endif
 195
 196 static const struct brport_attribute *brport_attrs[] = {
 197         &brport_attr_path_cost,
 198         &brport_attr_priority,
 199         &brport_attr_port_id,
 200         &brport_attr_port_no,
 201         &brport_attr_designated_root,
 202         &brport_attr_designated_bridge,
 203         &brport_attr_designated_port,
 204         &brport_attr_designated_cost,
 205         &brport_attr_state,
 206         &brport_attr_change_ack,
 207         &brport_attr_config_pending,
 208         &brport_attr_message_age_timer,
 209         &brport_attr_forward_delay_timer,
 210         &brport_attr_hold_timer,
 211         &brport_attr_flush,
 212         &brport_attr_hairpin_mode,
 213         &brport_attr_bpdu_guard,
 214         &brport_attr_root_block,
 215         &brport_attr_learning,
 216         &brport_attr_unicast_flood,
 217 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 218         &brport_attr_multicast_router,
 219         &brport_attr_multicast_fast_leave,
 220         &brport_attr_multicast_to_unicast,
 221 #endif
 222         &brport_attr_proxyarp,
 223         &brport_attr_proxyarp_wifi,
 224         &brport_attr_multicast_flood,
 225         &brport_attr_broadcast_flood,
 226         NULL
 227 };
 228
 229 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 230 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 231
 232 static ssize_t brport_show(struct kobject *kobj,
 233                            struct attribute *attr, char *buf)
 234 {
 235         struct brport_attribute *brport_attr = to_brport_attr(attr);
 236         struct net_bridge_port *p = to_brport(kobj);
 237
 238         if (!brport_attr->show)
 239                 return -EINVAL;
 240
 241         return brport_attr->show(p, buf);
 242 }
 243
 244 static ssize_t brport_store(struct kobject *kobj,
 245                             struct attribute *attr,
 246                             const char *buf, size_t count)
 247 {
 248         struct brport_attribute *brport_attr = to_brport_attr(attr);
 249         struct net_bridge_port *p = to_brport(kobj);
 250         ssize_t ret = -EINVAL;
 251         char *endp;
 252         unsigned long val;
 253
 254         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 255                 return -EPERM;
 256
 257         val = simple_strtoul(buf, &endp, 0);
 258         if (endp != buf) {
 259                 if (!rtnl_trylock())
 260                         return restart_syscall();
 261                 if (p->dev && p->br && brport_attr->store) {
 262                         spin_lock_bh(&p->br->lock);
 263                         ret = brport_attr->store(p, val);
 264                         spin_unlock_bh(&p->br->lock);
 265                         if (!ret) {
 266                                 br_ifinfo_notify(RTM_NEWLINK, p);
 267                                 ret = count;
 268                         }
 269                 }
 270                 rtnl_unlock();
 271         }
 272         return ret;
 273 }
 274
 275 const struct sysfs_ops brport_sysfs_ops = {
 276         .show = brport_show,
 277         .store = brport_store,
 278 };
 279
 280 /*
 281  * Add sysfs entries to ethernet device added to a bridge.
 282  * Creates a brport subdirectory with bridge attributes.
 283  * Puts symlink in bridge's brif subdirectory
 284  */
 285 int br_sysfs_addif(struct net_bridge_port *p)
 286 {
 287         struct net_bridge *br = p->br;
 288         const struct brport_attribute **a;
 289         int err;
 290
 291         err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
 292                                 SYSFS_BRIDGE_PORT_LINK);
 293         if (err)
 294                 return err;
 295
 296         for (a = brport_attrs; *a; ++a) {
 297                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 298                 if (err)
 299                         return err;
 300         }
 301
 302         strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 303         return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
 304 }
 305
 306 /* Rename bridge's brif symlink */
 307 int br_sysfs_renameif(struct net_bridge_port *p)
 308 {
 309         struct net_bridge *br = p->br;
 310         int err;
 311
 312         /* If a rename fails, the rollback will cause another
 313          * rename call with the existing name.
 314          */
 315         if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
 316                 return 0;
 317
 318         err = sysfs_rename_link(br->ifobj, &p->kobj,
 319                                 p->sysfs_name, p->dev->name);
 320         if (err)
 321                 netdev_notice(br->dev, "unable to rename link %s to %s",
 322                               p->sysfs_name, p->dev->name);
 323         else
 324                 strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 325
 326         return err;
 327 }