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(int *indices, int num)
  25 {
  26         struct net_device *dev;
  27         int i = 0;
  28
  29         for_each_netdev(&init_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 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
  85 {
  86         struct net_device *dev;
  87         int ret;
  88
  89         if (!capable(CAP_NET_ADMIN))
  90                 return -EPERM;
  91
  92         dev = dev_get_by_index(&init_net, ifindex);
  93         if (dev == NULL)
  94                 return -EINVAL;
  95
  96         if (isadd)
  97                 ret = br_add_if(br, dev);
  98         else
  99                 ret = br_del_if(br, dev);
 100
 101         dev_put(dev);
 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                 if (!capable(CAP_NET_ADMIN))
 192                         return -EPERM;
 193
 194                 spin_lock_bh(&br->lock);
 195                 br->bridge_hello_time = clock_t_to_jiffies(args[1]);
 196                 if (br_is_root_bridge(br))
 197                         br->hello_time = br->bridge_hello_time;
 198                 spin_unlock_bh(&br->lock);
 199                 return 0;
 200
 201         case BRCTL_SET_BRIDGE_MAX_AGE:
 202                 if (!capable(CAP_NET_ADMIN))
 203                         return -EPERM;
 204
 205                 spin_lock_bh(&br->lock);
 206                 br->bridge_max_age = clock_t_to_jiffies(args[1]);
 207                 if (br_is_root_bridge(br))
 208                         br->max_age = br->bridge_max_age;
 209                 spin_unlock_bh(&br->lock);
 210                 return 0;
 211
 212         case BRCTL_SET_AGEING_TIME:
 213                 if (!capable(CAP_NET_ADMIN))
 214                         return -EPERM;
 215
 216                 br->ageing_time = clock_t_to_jiffies(args[1]);
 217                 return 0;
 218
 219         case BRCTL_GET_PORT_INFO:
 220         {
 221                 struct __port_info p;
 222                 struct net_bridge_port *pt;
 223
 224                 rcu_read_lock();
 225                 if ((pt = br_get_port(br, args[2])) == NULL) {
 226                         rcu_read_unlock();
 227                         return -EINVAL;
 228                 }
 229
 230                 memset(&p, 0, sizeof(struct __port_info));
 231                 memcpy(&p.designated_root, &pt->designated_root, 8);
 232                 memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
 233                 p.port_id = pt->port_id;
 234                 p.designated_port = pt->designated_port;
 235                 p.path_cost = pt->path_cost;
 236                 p.designated_cost = pt->designated_cost;
 237                 p.state = pt->state;
 238                 p.top_change_ack = pt->topology_change_ack;
 239                 p.config_pending = pt->config_pending;
 240                 p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
 241                 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
 242                 p.hold_timer_value = br_timer_value(&pt->hold_timer);
 243
 244                 rcu_read_unlock();
 245
 246                 if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
 247                         return -EFAULT;
 248
 249                 return 0;
 250         }
 251
 252         case BRCTL_SET_BRIDGE_STP_STATE:
 253                 if (!capable(CAP_NET_ADMIN))
 254                         return -EPERM;
 255
 256                 br_stp_set_enabled(br, args[1]);
 257                 return 0;
 258
 259         case BRCTL_SET_BRIDGE_PRIORITY:
 260                 if (!capable(CAP_NET_ADMIN))
 261                         return -EPERM;
 262
 263                 spin_lock_bh(&br->lock);
 264                 br_stp_set_bridge_priority(br, args[1]);
 265                 spin_unlock_bh(&br->lock);
 266                 return 0;
 267
 268         case BRCTL_SET_PORT_PRIORITY:
 269         {
 270                 struct net_bridge_port *p;
 271                 int ret = 0;
 272
 273                 if (!capable(CAP_NET_ADMIN))
 274                         return -EPERM;
 275
 276                 if (args[2] >= (1<<(16-BR_PORT_BITS)))
 277                         return -ERANGE;
 278
 279                 spin_lock_bh(&br->lock);
 280                 if ((p = br_get_port(br, args[1])) == NULL)
 281                         ret = -EINVAL;
 282                 else
 283                         br_stp_set_port_priority(p, args[2]);
 284                 spin_unlock_bh(&br->lock);
 285                 return ret;
 286         }
 287
 288         case BRCTL_SET_PATH_COST:
 289         {
 290                 struct net_bridge_port *p;
 291                 int ret = 0;
 292
 293                 if (!capable(CAP_NET_ADMIN))
 294                         return -EPERM;
 295
 296                 if ((p = br_get_port(br, args[1])) == NULL)
 297                         ret = -EINVAL;
 298                 else
 299                         br_stp_set_path_cost(p, args[2]);
 300
 301                 return ret;
 302         }
 303
 304         case BRCTL_GET_FDB_ENTRIES:
 305                 return get_fdb_entries(br, (void __user *)args[1],
 306                                        args[2], args[3]);
 307         }
 308
 309         return -EOPNOTSUPP;
 310 }
 311
 312 static int old_deviceless(void __user *uarg)
 313 {
 314         unsigned long args[3];
 315
 316         if (copy_from_user(args, uarg, sizeof(args)))
 317                 return -EFAULT;
 318
 319         switch (args[0]) {
 320         case BRCTL_GET_VERSION:
 321                 return BRCTL_VERSION;
 322
 323         case BRCTL_GET_BRIDGES:
 324         {
 325                 int *indices;
 326                 int ret = 0;
 327
 328                 if (args[2] >= 2048)
 329                         return -ENOMEM;
 330                 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
 331                 if (indices == NULL)
 332                         return -ENOMEM;
 333
 334                 args[2] = get_bridge_ifindices(indices, args[2]);
 335
 336                 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
 337                         ? -EFAULT : args[2];
 338
 339                 kfree(indices);
 340                 return ret;
 341         }
 342
 343         case BRCTL_ADD_BRIDGE:
 344         case BRCTL_DEL_BRIDGE:
 345         {
 346                 char buf[IFNAMSIZ];
 347
 348                 if (!capable(CAP_NET_ADMIN))
 349                         return -EPERM;
 350
 351                 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
 352                         return -EFAULT;
 353
 354                 buf[IFNAMSIZ-1] = 0;
 355
 356                 if (args[0] == BRCTL_ADD_BRIDGE)
 357                         return br_add_bridge(buf);
 358
 359                 return br_del_bridge(buf);
 360         }
 361         }
 362
 363         return -EOPNOTSUPP;
 364 }
 365
 366 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
 367 {
 368         switch (cmd) {
 369         case SIOCGIFBR:
 370         case SIOCSIFBR:
 371                 return old_deviceless(uarg);
 372
 373         case SIOCBRADDBR:
 374         case SIOCBRDELBR:
 375         {
 376                 char buf[IFNAMSIZ];
 377
 378                 if (!capable(CAP_NET_ADMIN))
 379                         return -EPERM;
 380
 381                 if (copy_from_user(buf, uarg, IFNAMSIZ))
 382                         return -EFAULT;
 383
 384                 buf[IFNAMSIZ-1] = 0;
 385                 if (cmd == SIOCBRADDBR)
 386                         return br_add_bridge(buf);
 387
 388                 return br_del_bridge(buf);
 389         }
 390         }
 391         return -EOPNOTSUPP;
 392 }
 393
 394 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 395 {
 396         struct net_bridge *br = netdev_priv(dev);
 397
 398         switch(cmd) {
 399         case SIOCDEVPRIVATE:
 400                 return old_dev_ioctl(dev, rq, cmd);
 401
 402         case SIOCBRADDIF:
 403         case SIOCBRDELIF:
 404                 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
 405
 406         }
 407
 408         pr_debug("Bridge does not support ioctl 0x%x\n", cmd);
 409         return -EOPNOTSUPP;
 410 }