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 *net = dev_net(br->dev);
  89         struct net_device *dev;
  90         int ret;
  91
  92         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
  93                 return -EPERM;
  94
  95         dev = __dev_get_by_index(net, ifindex);
  96         if (dev == NULL)
  97                 return -EINVAL;
  98
  99         if (isadd)
 100                 ret = br_add_if(br, dev);
 101         else
 102                 ret = br_del_if(br, dev);
 103
 104         return ret;
 105 }
 106
 107 /*
 108  * Legacy ioctl's through SIOCDEVPRIVATE
 109  * This interface is deprecated because it was too difficult to
 110  * to do the translation for 32/64bit ioctl compatibility.
 111  */
 112 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 113 {
 114         struct net_bridge *br = netdev_priv(dev);
 115         unsigned long args[4];
 116
 117         if (copy_from_user(args, rq->ifr_data, sizeof(args)))
 118                 return -EFAULT;
 119
 120         switch (args[0]) {
 121         case BRCTL_ADD_IF:
 122         case BRCTL_DEL_IF:
 123                 return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF);
 124
 125         case BRCTL_GET_BRIDGE_INFO:
 126         {
 127                 struct __bridge_info b;
 128
 129                 memset(&b, 0, sizeof(struct __bridge_info));
 130                 rcu_read_lock();
 131                 memcpy(&b.designated_root, &br->designated_root, 8);
 132                 memcpy(&b.bridge_id, &br->bridge_id, 8);
 133                 b.root_path_cost = br->root_path_cost;
 134                 b.max_age = jiffies_to_clock_t(br->max_age);
 135                 b.hello_time = jiffies_to_clock_t(br->hello_time);
 136                 b.forward_delay = br->forward_delay;
 137                 b.bridge_max_age = br->bridge_max_age;
 138                 b.bridge_hello_time = br->bridge_hello_time;
 139                 b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay);
 140                 b.topology_change = br->topology_change;
 141                 b.topology_change_detected = br->topology_change_detected;
 142                 b.root_port = br->root_port;
 143
 144                 b.stp_enabled = (br->stp_enabled != BR_NO_STP);
 145                 b.ageing_time = jiffies_to_clock_t(br->ageing_time);
 146                 b.hello_timer_value = br_timer_value(&br->hello_timer);
 147                 b.tcn_timer_value = br_timer_value(&br->tcn_timer);
 148                 b.topology_change_timer_value = br_timer_value(&br->topology_change_timer);
 149                 b.gc_timer_value = br_timer_value(&br->gc_timer);
 150                 rcu_read_unlock();
 151
 152                 if (copy_to_user((void __user *)args[1], &b, sizeof(b)))
 153                         return -EFAULT;
 154
 155                 return 0;
 156         }
 157
 158         case BRCTL_GET_PORT_LIST:
 159         {
 160                 int num, *indices;
 161
 162                 num = args[2];
 163                 if (num < 0)
 164                         return -EINVAL;
 165                 if (num == 0)
 166                         num = 256;
 167                 if (num > BR_MAX_PORTS)
 168                         num = BR_MAX_PORTS;
 169
 170                 indices = kcalloc(num, sizeof(int), GFP_KERNEL);
 171                 if (indices == NULL)
 172                         return -ENOMEM;
 173
 174                 get_port_ifindices(br, indices, num);
 175                 if (copy_to_user((void __user *)args[1], indices, num*sizeof(int)))
 176                         num =  -EFAULT;
 177                 kfree(indices);
 178                 return num;
 179         }
 180
 181         case BRCTL_SET_BRIDGE_FORWARD_DELAY:
 182                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 183                         return -EPERM;
 184
 185                 return br_set_forward_delay(br, args[1]);
 186
 187         case BRCTL_SET_BRIDGE_HELLO_TIME:
 188                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 189                         return -EPERM;
 190
 191                 return br_set_hello_time(br, args[1]);
 192
 193         case BRCTL_SET_BRIDGE_MAX_AGE:
 194                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 195                         return -EPERM;
 196
 197                 return br_set_max_age(br, args[1]);
 198
 199         case BRCTL_SET_AGEING_TIME:
 200                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 201                         return -EPERM;
 202
 203                 return br_set_ageing_time(br, args[1]);
 204
 205         case BRCTL_GET_PORT_INFO:
 206         {
 207                 struct __port_info p;
 208                 struct net_bridge_port *pt;
 209
 210                 rcu_read_lock();
 211                 if ((pt = br_get_port(br, args[2])) == NULL) {
 212                         rcu_read_unlock();
 213                         return -EINVAL;
 214                 }
 215
 216                 memset(&p, 0, sizeof(struct __port_info));
 217                 memcpy(&p.designated_root, &pt->designated_root, 8);
 218                 memcpy(&p.designated_bridge, &pt->designated_bridge, 8);
 219                 p.port_id = pt->port_id;
 220                 p.designated_port = pt->designated_port;
 221                 p.path_cost = pt->path_cost;
 222                 p.designated_cost = pt->designated_cost;
 223                 p.state = pt->state;
 224                 p.top_change_ack = pt->topology_change_ack;
 225                 p.config_pending = pt->config_pending;
 226                 p.message_age_timer_value = br_timer_value(&pt->message_age_timer);
 227                 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer);
 228                 p.hold_timer_value = br_timer_value(&pt->hold_timer);
 229
 230                 rcu_read_unlock();
 231
 232                 if (copy_to_user((void __user *)args[1], &p, sizeof(p)))
 233                         return -EFAULT;
 234
 235                 return 0;
 236         }
 237
 238         case BRCTL_SET_BRIDGE_STP_STATE:
 239                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 240                         return -EPERM;
 241
 242                 br_stp_set_enabled(br, args[1]);
 243                 return 0;
 244
 245         case BRCTL_SET_BRIDGE_PRIORITY:
 246                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 247                         return -EPERM;
 248
 249                 br_stp_set_bridge_priority(br, args[1]);
 250                 return 0;
 251
 252         case BRCTL_SET_PORT_PRIORITY:
 253         {
 254                 struct net_bridge_port *p;
 255                 int ret;
 256
 257                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 258                         return -EPERM;
 259
 260                 spin_lock_bh(&br->lock);
 261                 if ((p = br_get_port(br, args[1])) == NULL)
 262                         ret = -EINVAL;
 263                 else
 264                         ret = br_stp_set_port_priority(p, args[2]);
 265                 spin_unlock_bh(&br->lock);
 266                 return ret;
 267         }
 268
 269         case BRCTL_SET_PATH_COST:
 270         {
 271                 struct net_bridge_port *p;
 272                 int ret;
 273
 274                 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 275                         return -EPERM;
 276
 277                 spin_lock_bh(&br->lock);
 278                 if ((p = br_get_port(br, args[1])) == NULL)
 279                         ret = -EINVAL;
 280                 else
 281                         ret = br_stp_set_path_cost(p, args[2]);
 282                 spin_unlock_bh(&br->lock);
 283
 284                 return ret;
 285         }
 286
 287         case BRCTL_GET_FDB_ENTRIES:
 288                 return get_fdb_entries(br, (void __user *)args[1],
 289                                        args[2], args[3]);
 290         }
 291
 292         return -EOPNOTSUPP;
 293 }
 294
 295 static int old_deviceless(struct net *net, void __user *uarg)
 296 {
 297         unsigned long args[3];
 298
 299         if (copy_from_user(args, uarg, sizeof(args)))
 300                 return -EFAULT;
 301
 302         switch (args[0]) {
 303         case BRCTL_GET_VERSION:
 304                 return BRCTL_VERSION;
 305
 306         case BRCTL_GET_BRIDGES:
 307         {
 308                 int *indices;
 309                 int ret = 0;
 310
 311                 if (args[2] >= 2048)
 312                         return -ENOMEM;
 313                 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL);
 314                 if (indices == NULL)
 315                         return -ENOMEM;
 316
 317                 args[2] = get_bridge_ifindices(net, indices, args[2]);
 318
 319                 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int))
 320                         ? -EFAULT : args[2];
 321
 322                 kfree(indices);
 323                 return ret;
 324         }
 325
 326         case BRCTL_ADD_BRIDGE:
 327         case BRCTL_DEL_BRIDGE:
 328         {
 329                 char buf[IFNAMSIZ];
 330
 331                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 332                         return -EPERM;
 333
 334                 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ))
 335                         return -EFAULT;
 336
 337                 buf[IFNAMSIZ-1] = 0;
 338
 339                 if (args[0] == BRCTL_ADD_BRIDGE)
 340                         return br_add_bridge(net, buf);
 341
 342                 return br_del_bridge(net, buf);
 343         }
 344         }
 345
 346         return -EOPNOTSUPP;
 347 }
 348
 349 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg)
 350 {
 351         switch (cmd) {
 352         case SIOCGIFBR:
 353         case SIOCSIFBR:
 354                 return old_deviceless(net, uarg);
 355
 356         case SIOCBRADDBR:
 357         case SIOCBRDELBR:
 358         {
 359                 char buf[IFNAMSIZ];
 360
 361                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 362                         return -EPERM;
 363
 364                 if (copy_from_user(buf, uarg, IFNAMSIZ))
 365                         return -EFAULT;
 366
 367                 buf[IFNAMSIZ-1] = 0;
 368                 if (cmd == SIOCBRADDBR)
 369                         return br_add_bridge(net, buf);
 370
 371                 return br_del_bridge(net, buf);
 372         }
 373         }
 374         return -EOPNOTSUPP;
 375 }
 376
 377 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 378 {
 379         struct net_bridge *br = netdev_priv(dev);
 380
 381         switch (cmd) {
 382         case SIOCDEVPRIVATE:
 383                 return old_dev_ioctl(dev, rq, cmd);
 384
 385         case SIOCBRADDIF:
 386         case SIOCBRDELIF:
 387                 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF);
 388
 389         }
 390
 391         br_debug(br, "Bridge does not support ioctl 0x%x\n", cmd);
 392         return -EOPNOTSUPP;
 393 }