1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Ioctl handler 4 * Linux ethernet bridge 5 * 6 * Authors: 7 * Lennert Buytenhek <buytenh@gnu.org> 8 */ 9 10 #include <linux/capability.h> 11 #include <linux/kernel.h> 12 #include <linux/if_bridge.h> 13 #include <linux/netdevice.h> 14 #include <linux/slab.h> 15 #include <linux/times.h> 16 #include <net/net_namespace.h> 17 #include <linux/uaccess.h> 18 #include "br_private.h" 19 20 static int get_bridge_ifindices(struct net *net, int *indices, int num) 21 { 22 struct net_device *dev; 23 int i = 0; 24 25 rcu_read_lock(); 26 for_each_netdev_rcu(net, dev) { 27 if (i >= num) 28 break; 29 if (dev->priv_flags & IFF_EBRIDGE) 30 indices[i++] = dev->ifindex; 31 } 32 rcu_read_unlock(); 33 34 return i; 35 } 36 37 /* called with RTNL */ 38 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num) 39 { 40 struct net_bridge_port *p; 41 42 list_for_each_entry(p, &br->port_list, list) { 43 if (p->port_no < num) 44 ifindices[p->port_no] = p->dev->ifindex; 45 } 46 } 47 48 /* 49 * Format up to a page worth of forwarding table entries 50 * userbuf -- where to copy result 51 * maxnum -- maximum number of entries desired 52 * (limited to a page for sanity) 53 * offset -- number of records to skip 54 */ 55 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf, 56 unsigned long maxnum, unsigned long offset) 57 { 58 int num; 59 void *buf; 60 size_t size; 61 62 /* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */ 63 if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry)) 64 maxnum = PAGE_SIZE/sizeof(struct __fdb_entry); 65 66 size = maxnum * sizeof(struct __fdb_entry); 67 68 buf = kmalloc(size, GFP_USER); 69 if (!buf) 70 return -ENOMEM; 71 72 num = br_fdb_fillbuf(br, buf, maxnum, offset); 73 if (num > 0) { 74 if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry))) 75 num = -EFAULT; 76 } 77 kfree(buf); 78 79 return num; 80 } 81 82 /* called with RTNL */ 83 static int add_del_if(struct net_bridge *br, int ifindex, int isadd) 84 { 85 struct net *net = dev_net(br->dev); 86 struct net_device *dev; 87 int ret; 88 89 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 90 return -EPERM; 91 92 dev = __dev_get_by_index(net, ifindex); 93 if (dev == NULL) 94 return -EINVAL; 95 96 if (isadd) 97 ret = br_add_if(br, dev, NULL); 98 else 99 ret = br_del_if(br, dev); 100 101 return ret; 102 } 103 104 /* 105 * Legacy ioctl's through SIOCDEVPRIVATE 106 * This interface is deprecated because it was too difficult to 107 * to do the translation for 32/64bit ioctl compatibility. 108 */ 109 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) 110 { 111 struct net_bridge *br = netdev_priv(dev); 112 struct net_bridge_port *p = NULL; 113 unsigned long args[4]; 114 int ret = -EOPNOTSUPP; 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_work.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 (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 182 return -EPERM; 183 184 ret = br_set_forward_delay(br, args[1]); 185 break; 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 ret = br_set_hello_time(br, args[1]); 192 break; 193 194 case BRCTL_SET_BRIDGE_MAX_AGE: 195 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 196 return -EPERM; 197 198 ret = br_set_max_age(br, args[1]); 199 break; 200 201 case BRCTL_SET_AGEING_TIME: 202 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 203 return -EPERM; 204 205 ret = br_set_ageing_time(br, args[1]); 206 break; 207 208 case BRCTL_GET_PORT_INFO: 209 { 210 struct __port_info p; 211 struct net_bridge_port *pt; 212 213 rcu_read_lock(); 214 if ((pt = br_get_port(br, args[2])) == NULL) { 215 rcu_read_unlock(); 216 return -EINVAL; 217 } 218 219 memset(&p, 0, sizeof(struct __port_info)); 220 memcpy(&p.designated_root, &pt->designated_root, 8); 221 memcpy(&p.designated_bridge, &pt->designated_bridge, 8); 222 p.port_id = pt->port_id; 223 p.designated_port = pt->designated_port; 224 p.path_cost = pt->path_cost; 225 p.designated_cost = pt->designated_cost; 226 p.state = pt->state; 227 p.top_change_ack = pt->topology_change_ack; 228 p.config_pending = pt->config_pending; 229 p.message_age_timer_value = br_timer_value(&pt->message_age_timer); 230 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer); 231 p.hold_timer_value = br_timer_value(&pt->hold_timer); 232 233 rcu_read_unlock(); 234 235 if (copy_to_user((void __user *)args[1], &p, sizeof(p))) 236 return -EFAULT; 237 238 return 0; 239 } 240 241 case BRCTL_SET_BRIDGE_STP_STATE: 242 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 243 return -EPERM; 244 245 ret = br_stp_set_enabled(br, args[1], NULL); 246 break; 247 248 case BRCTL_SET_BRIDGE_PRIORITY: 249 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 250 return -EPERM; 251 252 br_stp_set_bridge_priority(br, args[1]); 253 ret = 0; 254 break; 255 256 case BRCTL_SET_PORT_PRIORITY: 257 { 258 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 259 return -EPERM; 260 261 spin_lock_bh(&br->lock); 262 if ((p = br_get_port(br, args[1])) == NULL) 263 ret = -EINVAL; 264 else 265 ret = br_stp_set_port_priority(p, args[2]); 266 spin_unlock_bh(&br->lock); 267 break; 268 } 269 270 case BRCTL_SET_PATH_COST: 271 { 272 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 273 return -EPERM; 274 275 spin_lock_bh(&br->lock); 276 if ((p = br_get_port(br, args[1])) == NULL) 277 ret = -EINVAL; 278 else 279 ret = br_stp_set_path_cost(p, args[2]); 280 spin_unlock_bh(&br->lock); 281 break; 282 } 283 284 case BRCTL_GET_FDB_ENTRIES: 285 return get_fdb_entries(br, (void __user *)args[1], 286 args[2], args[3]); 287 } 288 289 if (!ret) { 290 if (p) 291 br_ifinfo_notify(RTM_NEWLINK, NULL, p); 292 else 293 netdev_state_change(br->dev); 294 } 295 296 return ret; 297 } 298 299 static int old_deviceless(struct net *net, void __user *uarg) 300 { 301 unsigned long args[3]; 302 303 if (copy_from_user(args, uarg, sizeof(args))) 304 return -EFAULT; 305 306 switch (args[0]) { 307 case BRCTL_GET_VERSION: 308 return BRCTL_VERSION; 309 310 case BRCTL_GET_BRIDGES: 311 { 312 int *indices; 313 int ret = 0; 314 315 if (args[2] >= 2048) 316 return -ENOMEM; 317 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL); 318 if (indices == NULL) 319 return -ENOMEM; 320 321 args[2] = get_bridge_ifindices(net, indices, args[2]); 322 323 ret = copy_to_user((void __user *)args[1], indices, args[2]*sizeof(int)) 324 ? -EFAULT : args[2]; 325 326 kfree(indices); 327 return ret; 328 } 329 330 case BRCTL_ADD_BRIDGE: 331 case BRCTL_DEL_BRIDGE: 332 { 333 char buf[IFNAMSIZ]; 334 335 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 336 return -EPERM; 337 338 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ)) 339 return -EFAULT; 340 341 buf[IFNAMSIZ-1] = 0; 342 343 if (args[0] == BRCTL_ADD_BRIDGE) 344 return br_add_bridge(net, buf); 345 346 return br_del_bridge(net, buf); 347 } 348 } 349 350 return -EOPNOTSUPP; 351 } 352 353 int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *uarg) 354 { 355 switch (cmd) { 356 case SIOCGIFBR: 357 case SIOCSIFBR: 358 return old_deviceless(net, uarg); 359 360 case SIOCBRADDBR: 361 case SIOCBRDELBR: 362 { 363 char buf[IFNAMSIZ]; 364 365 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 366 return -EPERM; 367 368 if (copy_from_user(buf, uarg, IFNAMSIZ)) 369 return -EFAULT; 370 371 buf[IFNAMSIZ-1] = 0; 372 if (cmd == SIOCBRADDBR) 373 return br_add_bridge(net, buf); 374 375 return br_del_bridge(net, buf); 376 } 377 } 378 return -EOPNOTSUPP; 379 } 380 381 int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) 382 { 383 struct net_bridge *br = netdev_priv(dev); 384 385 switch (cmd) { 386 case SIOCDEVPRIVATE: 387 return old_dev_ioctl(dev, rq, cmd); 388 389 case SIOCBRADDIF: 390 case SIOCBRDELIF: 391 return add_del_if(br, rq->ifr_ifindex, cmd == SIOCBRADDIF); 392 393 } 394 395 br_debug(br, "Bridge does not support ioctl 0x%x\n", cmd); 396 return -EOPNOTSUPP; 397 } 398