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/slab.h>
  19 #include <linux/times.h>
  20 #include <net/net_namespace.h>
  21 #include <asm/uaccess.h>
  22 #include "br_private.h"
  23
  24 /* called with RTNL */
  25 static int get_bridge_ifindices(struct net *net, int *indices, int num)
  26 {
  27         struct net_device *dev;
  28         int i = 0;
  29
  30         for_each_netdev(net, dev) {
  31                 if (i >= num)
  32                         break;
  33                 if (dev->priv_flags & IFF_EBRIDGE)
  34                         indices[i++] = dev->ifindex;
  35         }
  36
  37         return i;
  38 }
  39
  40 /* called with RTNL */
  41 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num)
  42 {
  43         struct net_bridge_port *p;
  44
  45         list_for_each_entry(p, &br->port_list, list) {
  46                 if (p->port_no < num)
  47                         ifindices[p->port_no] = p->dev->ifindex;
  48         }
  49 }
  50
  51 /*
  52  * Format up to a page worth of forwarding table entries
  53  * userbuf -- where to copy result
  54  * maxnum  -- maximum number of entries desired
  55  *            (limited to a page for sanity)
  56  * offset  -- number of records to skip
  57  */
  58 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
  59                            unsigned long maxnum, unsigned long offset)
  60 {
  61         int num;
  62         void *buf;
  63         size_t size;
  64
  65         /* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */
  66         if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry))
  67                 maxnum = PAGE_SIZE/sizeof(struct __fdb_entry);
  68
  69         size = maxnum * sizeof(struct __fdb_entry);
  70
  71         buf = kmalloc(size, GFP_USER);
  72         if (!buf)
  73                 return -ENOMEM;
  74
  75         num = br_fdb_fillbuf(br, buf, maxnum, offset);
  76         if (num > 0) {
  77                 if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry)))
  78                         num = -EFAULT;
  79         }
  80         kfree(buf);
  81
  82         return num;
  83 }
  84
  85 /* called with RTNL */
  86 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
  87 {
  88         struct net_device *dev;
  89         int ret;
  90
  91         if (!capable(CAP_NET_ADMIN))
  92                 return -EPERM;
  93
  94         dev = __dev_get_by_index(dev_net(br->dev), ifindex);
  95         if (dev == NULL)
  96                 return -EINVAL;
  97
  98         if (isadd)
  99                 ret = br_add_if(br, dev);
 100         else
 101                 ret = br_del_if(br, dev);
 102
 103         return ret;
 104 }
 105
 106 /*
 107  * Legacy ioctl's through SIOCDEVPRIVATE
 108  * This interface is deprecated because it was too difficult to
 109  * to do the translation for 32/64bit ioctl compatability.
 110  */
 111 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 112 {
 113         struct net_bridge *br = netdev_priv(dev);
 114         unsigned long args[4];
 115
 116         if (copy_from_user(args, rq->ifr_data, sizeof(args)))
 117                 return -EFAULT;
 118
 119         switch (args[0]) {
 120         case BRCTL_ADD_IF:
 121         case BRCTL_DEL_IF:
 122                 return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
 123
 124         case BRCTL_GET_BRIDGE_INFO:
 125         {
 126                 struct __bridge_info b;
 127
 128                 memset(&b, 0, sizeof(struct __bridge_info));
 129                 rcu_read_lock();
 130                 memcpy(&b.designated_root, &br->designated_root, 8);
 131                 memcpy(&b.bridge_id, &br->bridge_id, 8);
 132                 b.root_path_cost = br->root_path_cost;
 133                 b.max_age = jiffies_to_clock_t(br->max_age);
 134                 b.hello_time = jiffies_to_clock_t(br->hello_time);
 135                 b.forward_delay = br->forward_delay;
 136                 b.bridge_max_age = br->bridge_max_age;
 137                 b.bridge_hello_time = br->bridge_hello_time;
 138                 b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
 139                 b.topology_change = br->topology_change;
 140                 b.topology_change_detected = br->topology_change_detected;
 141                 b.root_port = br->root_port;
 142
 143                 b.stp_enabled = (br->stp_enabled != BR_NO_STP);
 144                 b.ageing_time = jiffies_to_clock_t(br->ageing_time);
 145                 b.hello_timer_value = br_timer_value(&br->hello_timer);
 146                 b.tcn_timer_value = br_timer_value(&br->tcn_timer);
 147                 b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
 148                 b.gc_timer_value = br_timer_value(&br->gc_timer);
 149                 rcu_read_unlock();
 150
 151                 if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
 152                         return -EFAULT;
 153
 154                 return 0;
 155         }
 156
 157         case BRCTL_GET_PORT_LIST:
 158         {
 159                 int num, *indices;
 160
 161                 num = args[2];
 162                 if (num < 0)
 163                         return -EINVAL;
 164                 if (num == 0)
 165                         num = 256;
 166                 if (num > BR_MAX_PORTS)
 167                         num = BR_MAX_PORTS;
 168
 169                 indices = kcalloc(num, sizeof(int), GFP_KERNEL);
 170                 if (indices == NULL)
 171                         return -ENOMEM;
 172
 173                 get_port_ifindices(br, indices, num);
 174                 if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
 175                         num =  -EFAULT;
 176                 kfree(indices);
 177                 return num;
 178         }
 179
 180         case BRCTL_SET_BRIDGE_FORWARD_DELAY:
 181                 if (!capable(CAP_NET_ADMIN))
 182                         return -EPERM;
 183
 184                 spin_lock_bh(&br->lock);
 185                 br->bridge_forward_delay = clock_t_to_jiffies(args[1]);
 186                 if (br_is_root_bridge(br))
 187                         br->forward_delay = br->bridge_forward_delay;
 188                 spin_unlock_bh(&br->lock);
 189                 return 0;
 190
 191         case BRCTL_SET_BRIDGE_HELLO_TIME:
 192         {
 193                 unsigned long t = clock_t_to_jiffies(args[1]);
 194                 if (!capable(CAP_NET_ADMIN))
 195                         return -EPERM;
 196
 197                 if (t < HZ)
 198                         return -EINVAL;
 199
 200                 spin_lock_bh(&br->lock);
 201                 br->bridge_hello_time = t;
 202                 if (br_is_root_bridge(br))
 203                         br->hello_time = br->bridge_hello_time;
 204                 spin_unlock_bh(&br->lock);
 205                 return 0;
 206         }
 207
 208         case BRCTL_SET_BRIDGE_MAX_AGE:
 209                 if (!capable(CAP_NET_ADMIN))
 210                         return -EPERM;
 211
 212                 spin_lock_bh(&br->lock);
 213                 br->bridge_max_age = clock_t_to_jiffies(args[1]);
 214                 if (br_is_root_bridge(br))
 215                         br->max_age = br->bridge_max_age;
 216                 spin_unlock_bh(&br->lock);
 217                 return 0;
 218
 219         case BRCTL_SET_AGEING_TIME:
 220                 if (!capable(CAP_NET_ADMIN))
 221                         return -EPERM;
 222
 223                 br->ageing_time = clock_t_to_jiffies(args[1]);
 224                 return 0;
 225
 226         case BRCTL_GET_PORT_INFO:
 227         {
 228                 struct __port_info p;
 229                 struct net_bridge_port *pt;
 230
 231                 rcu_read_lock();
 232                 if ((pt = br_get_port(br, args[2])) == NULL) {
 233                         rcu_read_unlock();
 234                         return -EINVAL;
 235                 }
 236
 237                 memset(&p, 0, sizeof(struct __port_info));
 238                 memcpy(&p.designated_root, &pt->designated_root, 8);
 239                 memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
 240                 p.port_id = pt->port_id;
 241                 p.designated_port = pt->designated_port;
 242                 p.path_cost = pt->path_cost;
 243                 p.designated_cost = pt->designated_cost;
 244                 p.state = pt->state;
 245                 p.top_change_ack = pt->topology_change_ack;
 246                 p.config_pending = pt->config_pending;
 247                 p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
 248                 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
 249                 p.hold_timer_value = br_timer_value(&pt->hold_timer);
 250
 251                 rcu_read_unlock();
 252
 253                 if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
 254                         return -EFAULT;
 255
 256                 return 0;
 257         }
 258
 259         case BRCTL_SET_BRIDGE_STP_STATE:
 260                 if (!capable(CAP_NET_ADMIN))
 261                         return -EPERM;
 262
 263                 br_stp_set_enabled(br, args[1]);
 264                 return 0;
 265
 266         case BRCTL_SET_BRIDGE_PRIORITY:
 267                 if (!capable(CAP_NET_ADMIN))
 268                         return -EPERM;
 269
 270                 spin_lock_bh(&br->lock);
 271                 br_stp_set_bridge_priority(br, args[1]);
 272                 spin_unlock_bh(&br->lock);
 273                 return 0;
 274
 275         case BRCTL_SET_PORT_PRIORITY:
 276         {
 277                 struct net_bridge_port *p;
 278                 int ret = 0;
 279
 280                 if (!capable(CAP_NET_ADMIN))
 281                         return -EPERM;
 282
 283                 if (args[2] >= (1<<(16-BR_PORT_BITS)))
 284                         return -ERANGE;
 285
 286                 spin_lock_bh(&br->lock);
 287                 if ((p = br_get_port(br, args[1])) == NULL)
 288                         ret = -EINVAL;
 289                 else
 290                         br_stp_set_port_priority(p, args[2]);
 291                 spin_unlock_bh(&br->lock);
 292                 return ret;
 293         }
 294
 295         case BRCTL_SET_PATH_COST:
 296         {
 297                 struct net_bridge_port *p;
 298                 int ret = 0;
 299
 300                 if (!capable(CAP_NET_ADMIN))
 301                         return -EPERM;
 302
 303                 if ((p = br_get_port(br, args[1])) == NULL)
 304                         ret = -EINVAL;
 305                 else
 306                         br_stp_set_path_cost(p, args[2]);
 307
 308                 return ret;
 309         }
 310
 311         case BRCTL_GET_FDB_ENTRIES:
 312                 return get_fdb_entries(br, (void __user *)args[1],
 313                                        args[2], args[3]);
 314         }
 315
 316         return -EOPNOTSUPP;
 317 }
 318
 319 static int old_deviceless(struct net *net, void __user *uarg)
 320 {
 321         unsigned long args[3];
 322
 323         if (copy_from_user(args, uarg, sizeof(args)))
 324                 return -EFAULT;
 325
 326         switch (args[0]) {
 327         case BRCTL_GET_VERSION:
 328                 return BRCTL_VERSION;
 329
 330         case BRCTL_GET_BRIDGES:
 331         {
 332                 int *indices;
 333                 int ret = 0;
 334
 335                 if (args[2] >= 2048)
 336                         return -ENOMEM;
 337                 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
 338                 if (indices == NULL)
 339                         return -ENOMEM;
 340
 341                 args[2] = get_bridge_ifindices(net, indices, args[2]);
 342
 343                 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
 344                         ? -EFAULT : args[2];
 345
 346                 kfree(indices);
 347                 return ret;
 348         }
 349
 350         case BRCTL_ADD_BRIDGE:
 351         case BRCTL_DEL_BRIDGE:
 352         {
 353                 char buf[IFNAMSIZ];
 354
 355                 if (!capable(CAP_NET_ADMIN))
 356                         return -EPERM;
 357
 358                 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
 359                         return -EFAULT;
 360
 361                 buf[IFNAMSIZ-1] = 0;
 362
 363                 if (args[0] == BRCTL_ADD_BRIDGE)
 364                         return br_add_bridge(net, buf);
 365
 366                 return br_del_bridge(net, buf);
 367         }
 368         }
 369
 370         return -EOPNOTSUPP;
 371 }
 372
 373 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
 374 {
 375         switch (cmd) {
 376         case SIOCGIFBR:
 377         case SIOCSIFBR:
 378                 return old_deviceless(net, uarg);
 379
 380         case SIOCBRADDBR:
 381         case SIOCBRDELBR:
 382         {
 383                 char buf[IFNAMSIZ];
 384
 385                 if (!capable(CAP_NET_ADMIN))
 386                         return -EPERM;
 387
 388                 if (copy_from_user(buf, uarg, IFNAMSIZ))
 389                         return -EFAULT;
 390
 391                 buf[IFNAMSIZ-1] = 0;
 392                 if (cmd == SIOCBRADDBR)
 393                         return br_add_bridge(net, buf);
 394
 395                 return br_del_bridge(net, buf);
 396         }
 397         }
 398         return -EOPNOTSUPP;
 399 }
 400
 401 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 402 {
 403         struct net_bridge *br = netdev_priv(dev);
 404
 405         switch(cmd) {
 406         case SIOCDEVPRIVATE:
 407                 return old_dev_ioctl(dev, rq, cmd);
 408
 409         case SIOCBRADDIF:
 410         case SIOCBRDELIF:
 411                 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
 412
 413         }
 414
 415         pr_debug("Bridge does not support ioctl 0x%x\n", cmd);
 416         return -EOPNOTSUPP;
 417 }