net/bridge/br_ioctl.c

   1 /*
   2  *      Ioctl handler
   3  *      Linux ethernet bridge
   4  *
   5  *      Authors:
   6  *      Lennert Buytenhek               <buytenh@gnu.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/if_bridge.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/times.h>
  19 #include <net/net_namespace.h>
  20 #include <asm/uaccess.h>
  21 #include "br_private.h"
  22
  23 /* called with RTNL */
  24 static int get_bridge_ifindices(struct net *net, int *indices, int num)
  25 {
  26         struct net_device *dev;
  27         int i = 0;
  28
  29         for_each_netdev(net, dev) {
  30                 if (i >= num)
  31                         break;
  32                 if (dev->priv_flags & IFF_EBRIDGE)
  33                         indices[i++] = dev->ifindex;
  34         }
  35
  36         return i;
  37 }
  38
  39 /* called with RTNL */
  40 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num)
  41 {
  42         struct net_bridge_port *p;
  43
  44         list_for_each_entry(p, &br->port_list, list) {
  45                 if (p->port_no < num)
  46                         ifindices[p->port_no] = p->dev->ifindex;
  47         }
  48 }
  49
  50 /*
  51  * Format up to a page worth of forwarding table entries
  52  * userbuf -- where to copy result
  53  * maxnum  -- maximum number of entries desired
  54  *            (limited to a page for sanity)
  55  * offset  -- number of records to skip
  56  */
  57 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
  58                            unsigned long maxnum, unsigned long offset)
  59 {
  60         int num;
  61         void *buf;
  62         size_t size;
  63
  64         /* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */
  65         if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry))
  66                 maxnum = PAGE_SIZE/sizeof(struct __fdb_entry);
  67
  68         size = maxnum * sizeof(struct __fdb_entry);
  69
  70         buf = kmalloc(size, GFP_USER);
  71         if (!buf)
  72                 return -ENOMEM;
  73
  74         num = br_fdb_fillbuf(br, buf, maxnum, offset);
  75         if (num > 0) {
  76                 if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry)))
  77                         num = -EFAULT;
  78         }
  79         kfree(buf);
  80
  81         return num;
  82 }
  83
  84 /* called with RTNL */
  85 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
  86 {
  87         struct net_device *dev;
  88         int ret;
  89
  90         if (!capable(CAP_NET_ADMIN))
  91                 return -EPERM;
  92
  93         dev = __dev_get_by_index(dev_net(br->dev), ifindex);
  94         if (dev == NULL)
  95                 return -EINVAL;
  96
  97         if (isadd)
  98                 ret = br_add_if(br, dev);
  99         else
 100                 ret = br_del_if(br, dev);
 101
 102         return ret;
 103 }
 104
 105 /*
 106  * Legacy ioctl's through SIOCDEVPRIVATE
 107  * This interface is deprecated because it was too difficult to
 108  * to do the translation for 32/64bit ioctl compatability.
 109  */
 110 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 111 {
 112         struct net_bridge *br = netdev_priv(dev);
 113         unsigned long args[4];
 114
 115         if (copy_from_user(args, rq->ifr_data, sizeof(args)))
 116                 return -EFAULT;
 117
 118         switch (args[0]) {
 119         case BRCTL_ADD_IF:
 120         case BRCTL_DEL_IF:
 121                 return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
 122
 123         case BRCTL_GET_BRIDGE_INFO:
 124         {
 125                 struct __bridge_info b;
 126
 127                 memset(&b, 0, sizeof(struct __bridge_info));
 128                 rcu_read_lock();
 129                 memcpy(&b.designated_root, &br->designated_root, 8);
 130                 memcpy(&b.bridge_id, &br->bridge_id, 8);
 131                 b.root_path_cost = br->root_path_cost;
 132                 b.max_age = jiffies_to_clock_t(br->max_age);
 133                 b.hello_time = jiffies_to_clock_t(br->hello_time);
 134                 b.forward_delay = br->forward_delay;
 135                 b.bridge_max_age = br->bridge_max_age;
 136                 b.bridge_hello_time = br->bridge_hello_time;
 137                 b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
 138                 b.topology_change = br->topology_change;
 139                 b.topology_change_detected = br->topology_change_detected;
 140                 b.root_port = br->root_port;
 141
 142                 b.stp_enabled = (br->stp_enabled != BR_NO_STP);
 143                 b.ageing_time = jiffies_to_clock_t(br->ageing_time);
 144                 b.hello_timer_value = br_timer_value(&br->hello_timer);
 145                 b.tcn_timer_value = br_timer_value(&br->tcn_timer);
 146                 b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
 147                 b.gc_timer_value = br_timer_value(&br->gc_timer);
 148                 rcu_read_unlock();
 149
 150                 if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
 151                         return -EFAULT;
 152
 153                 return 0;
 154         }
 155
 156         case BRCTL_GET_PORT_LIST:
 157         {
 158                 int num, *indices;
 159
 160                 num = args[2];
 161                 if (num < 0)
 162                         return -EINVAL;
 163                 if (num == 0)
 164                         num = 256;
 165                 if (num > BR_MAX_PORTS)
 166                         num = BR_MAX_PORTS;
 167
 168                 indices = kcalloc(num, sizeof(int), GFP_KERNEL);
 169                 if (indices == NULL)
 170                         return -ENOMEM;
 171
 172                 get_port_ifindices(br, indices, num);
 173                 if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
 174                         num =  -EFAULT;
 175                 kfree(indices);
 176                 return num;
 177         }
 178
 179         case BRCTL_SET_BRIDGE_FORWARD_DELAY:
 180                 if (!capable(CAP_NET_ADMIN))
 181                         return -EPERM;
 182
 183                 spin_lock_bh(&br->lock);
 184                 br->bridge_forward_delay = clock_t_to_jiffies(args[1]);
 185                 if (br_is_root_bridge(br))
 186                         br->forward_delay = br->bridge_forward_delay;
 187                 spin_unlock_bh(&br->lock);
 188                 return 0;
 189
 190         case BRCTL_SET_BRIDGE_HELLO_TIME:
 191         {
 192                 unsigned long t = clock_t_to_jiffies(args[1]);
 193                 if (!capable(CAP_NET_ADMIN))
 194                         return -EPERM;
 195
 196                 if (t < HZ)
 197                         return -EINVAL;
 198
 199                 spin_lock_bh(&br->lock);
 200                 br->bridge_hello_time = t;
 201                 if (br_is_root_bridge(br))
 202                         br->hello_time = br->bridge_hello_time;
 203                 spin_unlock_bh(&br->lock);
 204                 return 0;
 205         }
 206
 207         case BRCTL_SET_BRIDGE_MAX_AGE:
 208                 if (!capable(CAP_NET_ADMIN))
 209                         return -EPERM;
 210
 211                 spin_lock_bh(&br->lock);
 212                 br->bridge_max_age = clock_t_to_jiffies(args[1]);
 213                 if (br_is_root_bridge(br))
 214                         br->max_age = br->bridge_max_age;
 215                 spin_unlock_bh(&br->lock);
 216                 return 0;
 217
 218         case BRCTL_SET_AGEING_TIME:
 219                 if (!capable(CAP_NET_ADMIN))
 220                         return -EPERM;
 221
 222                 br->ageing_time = clock_t_to_jiffies(args[1]);
 223                 return 0;
 224
 225         case BRCTL_GET_PORT_INFO:
 226         {
 227                 struct __port_info p;
 228                 struct net_bridge_port *pt;
 229
 230                 rcu_read_lock();
 231                 if ((pt = br_get_port(br, args[2])) == NULL) {
 232                         rcu_read_unlock();
 233                         return -EINVAL;
 234                 }
 235
 236                 memset(&p, 0, sizeof(struct __port_info));
 237                 memcpy(&p.designated_root, &pt->designated_root, 8);
 238                 memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
 239                 p.port_id = pt->port_id;
 240                 p.designated_port = pt->designated_port;
 241                 p.path_cost = pt->path_cost;
 242                 p.designated_cost = pt->designated_cost;
 243                 p.state = pt->state;
 244                 p.top_change_ack = pt->topology_change_ack;
 245                 p.config_pending = pt->config_pending;
 246                 p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
 247                 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
 248                 p.hold_timer_value = br_timer_value(&pt->hold_timer);
 249
 250                 rcu_read_unlock();
 251
 252                 if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
 253                         return -EFAULT;
 254
 255                 return 0;
 256         }
 257
 258         case BRCTL_SET_BRIDGE_STP_STATE:
 259                 if (!capable(CAP_NET_ADMIN))
 260                         return -EPERM;
 261
 262                 br_stp_set_enabled(br, args[1]);
 263                 return 0;
 264
 265         case BRCTL_SET_BRIDGE_PRIORITY:
 266                 if (!capable(CAP_NET_ADMIN))
 267                         return -EPERM;
 268
 269                 spin_lock_bh(&br->lock);
 270                 br_stp_set_bridge_priority(br, args[1]);
 271                 spin_unlock_bh(&br->lock);
 272                 return 0;
 273
 274         case BRCTL_SET_PORT_PRIORITY:
 275         {
 276                 struct net_bridge_port *p;
 277                 int ret = 0;
 278
 279                 if (!capable(CAP_NET_ADMIN))
 280                         return -EPERM;
 281
 282                 if (args[2] >= (1<<(16-BR_PORT_BITS)))
 283                         return -ERANGE;
 284
 285                 spin_lock_bh(&br->lock);
 286                 if ((p = br_get_port(br, args[1])) == NULL)
 287                         ret = -EINVAL;
 288                 else
 289                         br_stp_set_port_priority(p, args[2]);
 290                 spin_unlock_bh(&br->lock);
 291                 return ret;
 292         }
 293
 294         case BRCTL_SET_PATH_COST:
 295         {
 296                 struct net_bridge_port *p;
 297                 int ret = 0;
 298
 299                 if (!capable(CAP_NET_ADMIN))
 300                         return -EPERM;
 301
 302                 if ((p = br_get_port(br, args[1])) == NULL)
 303                         ret = -EINVAL;
 304                 else
 305                         br_stp_set_path_cost(p, args[2]);
 306
 307                 return ret;
 308         }
 309
 310         case BRCTL_GET_FDB_ENTRIES:
 311                 return get_fdb_entries(br, (void __user *)args[1],
 312                                        args[2], args[3]);
 313         }
 314
 315         return -EOPNOTSUPP;
 316 }
 317
 318 static int old_deviceless(struct net *net, void __user *uarg)
 319 {
 320         unsigned long args[3];
 321
 322         if (copy_from_user(args, uarg, sizeof(args)))
 323                 return -EFAULT;
 324
 325         switch (args[0]) {
 326         case BRCTL_GET_VERSION:
 327                 return BRCTL_VERSION;
 328
 329         case BRCTL_GET_BRIDGES:
 330         {
 331                 int *indices;
 332                 int ret = 0;
 333
 334                 if (args[2] >= 2048)
 335                         return -ENOMEM;
 336                 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
 337                 if (indices == NULL)
 338                         return -ENOMEM;
 339
 340                 args[2] = get_bridge_ifindices(net, indices, args[2]);
 341
 342                 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
 343                         ? -EFAULT : args[2];
 344
 345                 kfree(indices);
 346                 return ret;
 347         }
 348
 349         case BRCTL_ADD_BRIDGE:
 350         case BRCTL_DEL_BRIDGE:
 351         {
 352                 char buf[IFNAMSIZ];
 353
 354                 if (!capable(CAP_NET_ADMIN))
 355                         return -EPERM;
 356
 357                 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
 358                         return -EFAULT;
 359
 360                 buf[IFNAMSIZ-1] = 0;
 361
 362                 if (args[0] == BRCTL_ADD_BRIDGE)
 363                         return br_add_bridge(net, buf);
 364
 365                 return br_del_bridge(net, buf);
 366         }
 367         }
 368
 369         return -EOPNOTSUPP;
 370 }
 371
 372 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
 373 {
 374         switch (cmd) {
 375         case SIOCGIFBR:
 376         case SIOCSIFBR:
 377                 return old_deviceless(net, uarg);
 378
 379         case SIOCBRADDBR:
 380         case SIOCBRDELBR:
 381         {
 382                 char buf[IFNAMSIZ];
 383
 384                 if (!capable(CAP_NET_ADMIN))
 385                         return -EPERM;
 386
 387                 if (copy_from_user(buf, uarg, IFNAMSIZ))
 388                         return -EFAULT;
 389
 390                 buf[IFNAMSIZ-1] = 0;
 391                 if (cmd == SIOCBRADDBR)
 392                         return br_add_bridge(net, buf);
 393
 394                 return br_del_bridge(net, buf);
 395         }
 396         }
 397         return -EOPNOTSUPP;
 398 }
 399
 400 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 401 {
 402         struct net_bridge *br = netdev_priv(dev);
 403
 404         switch(cmd) {
 405         case SIOCDEVPRIVATE:
 406                 return old_dev_ioctl(dev, rq, cmd);
 407
 408         case SIOCBRADDIF:
 409         case SIOCBRDELIF:
 410                 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
 411
 412         }
 413
 414         pr_debug("Bridge does not support ioctl 0x%x\n", cmd);
 415         return -EOPNOTSUPP;
 416 }