1 /* 2 * Bridge netlink control interface 3 * 4 * Authors: 5 * Stephen Hemminger <shemminger@osdl.org> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/slab.h> 15 #include <linux/etherdevice.h> 16 #include <net/rtnetlink.h> 17 #include <net/net_namespace.h> 18 #include <net/sock.h> 19 #include <uapi/linux/if_bridge.h> 20 21 #include "br_private.h" 22 #include "br_private_stp.h" 23 24 static inline size_t br_port_info_size(void) 25 { 26 return nla_total_size(1) /* IFLA_BRPORT_STATE */ 27 + nla_total_size(2) /* IFLA_BRPORT_PRIORITY */ 28 + nla_total_size(4) /* IFLA_BRPORT_COST */ 29 + nla_total_size(1) /* IFLA_BRPORT_MODE */ 30 + nla_total_size(1) /* IFLA_BRPORT_GUARD */ 31 + nla_total_size(1) /* IFLA_BRPORT_PROTECT */ 32 + nla_total_size(1) /* IFLA_BRPORT_FAST_LEAVE */ 33 + 0; 34 } 35 36 static inline size_t br_nlmsg_size(void) 37 { 38 return NLMSG_ALIGN(sizeof(struct ifinfomsg)) 39 + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */ 40 + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */ 41 + nla_total_size(4) /* IFLA_MASTER */ 42 + nla_total_size(4) /* IFLA_MTU */ 43 + nla_total_size(4) /* IFLA_LINK */ 44 + nla_total_size(1) /* IFLA_OPERSTATE */ 45 + nla_total_size(br_port_info_size()); /* IFLA_PROTINFO */ 46 } 47 48 static int br_port_fill_attrs(struct sk_buff *skb, 49 const struct net_bridge_port *p) 50 { 51 u8 mode = !!(p->flags & BR_HAIRPIN_MODE); 52 53 if (nla_put_u8(skb, IFLA_BRPORT_STATE, p->state) || 54 nla_put_u16(skb, IFLA_BRPORT_PRIORITY, p->priority) || 55 nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) || 56 nla_put_u8(skb, IFLA_BRPORT_MODE, mode) || 57 nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) || 58 nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) || 59 nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE))) 60 return -EMSGSIZE; 61 62 return 0; 63 } 64 65 /* 66 * Create one netlink message for one interface 67 * Contains port and master info as well as carrier and bridge state. 68 */ 69 static int br_fill_ifinfo(struct sk_buff *skb, 70 const struct net_bridge_port *port, 71 u32 pid, u32 seq, int event, unsigned int flags, 72 u32 filter_mask, const struct net_device *dev) 73 { 74 const struct net_bridge *br; 75 struct ifinfomsg *hdr; 76 struct nlmsghdr *nlh; 77 u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN; 78 79 if (port) 80 br = port->br; 81 else 82 br = netdev_priv(dev); 83 84 br_debug(br, "br_fill_info event %d port %s master %s\n", 85 event, dev->name, br->dev->name); 86 87 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags); 88 if (nlh == NULL) 89 return -EMSGSIZE; 90 91 hdr = nlmsg_data(nlh); 92 hdr->ifi_family = AF_BRIDGE; 93 hdr->__ifi_pad = 0; 94 hdr->ifi_type = dev->type; 95 hdr->ifi_index = dev->ifindex; 96 hdr->ifi_flags = dev_get_flags(dev); 97 hdr->ifi_change = 0; 98 99 if (nla_put_string(skb, IFLA_IFNAME, dev->name) || 100 nla_put_u32(skb, IFLA_MASTER, br->dev->ifindex) || 101 nla_put_u32(skb, IFLA_MTU, dev->mtu) || 102 nla_put_u8(skb, IFLA_OPERSTATE, operstate) || 103 (dev->addr_len && 104 nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) || 105 (dev->ifindex != dev->iflink && 106 nla_put_u32(skb, IFLA_LINK, dev->iflink))) 107 goto nla_put_failure; 108 109 if (event == RTM_NEWLINK && port) { 110 struct nlattr *nest 111 = nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED); 112 113 if (nest == NULL || br_port_fill_attrs(skb, port) < 0) 114 goto nla_put_failure; 115 nla_nest_end(skb, nest); 116 } 117 118 /* Check if the VID information is requested */ 119 if (filter_mask & RTEXT_FILTER_BRVLAN) { 120 struct nlattr *af; 121 const struct net_port_vlans *pv; 122 struct bridge_vlan_info vinfo; 123 u16 vid; 124 u16 pvid; 125 126 if (port) 127 pv = nbp_get_vlan_info(port); 128 else 129 pv = br_get_vlan_info(br); 130 131 if (!pv || bitmap_empty(pv->vlan_bitmap, BR_VLAN_BITMAP_LEN)) 132 goto done; 133 134 af = nla_nest_start(skb, IFLA_AF_SPEC); 135 if (!af) 136 goto nla_put_failure; 137 138 pvid = br_get_pvid(pv); 139 for_each_set_bit(vid, pv->vlan_bitmap, BR_VLAN_BITMAP_LEN) { 140 vinfo.vid = vid; 141 vinfo.flags = 0; 142 if (vid == pvid) 143 vinfo.flags |= BRIDGE_VLAN_INFO_PVID; 144 145 if (test_bit(vid, pv->untagged_bitmap)) 146 vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED; 147 148 if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO, 149 sizeof(vinfo), &vinfo)) 150 goto nla_put_failure; 151 } 152 153 nla_nest_end(skb, af); 154 } 155 156 done: 157 return nlmsg_end(skb, nlh); 158 159 nla_put_failure: 160 nlmsg_cancel(skb, nlh); 161 return -EMSGSIZE; 162 } 163 164 /* 165 * Notify listeners of a change in port information 166 */ 167 void br_ifinfo_notify(int event, struct net_bridge_port *port) 168 { 169 struct net *net; 170 struct sk_buff *skb; 171 int err = -ENOBUFS; 172 173 if (!port) 174 return; 175 176 net = dev_net(port->dev); 177 br_debug(port->br, "port %u(%s) event %d\n", 178 (unsigned int)port->port_no, port->dev->name, event); 179 180 skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC); 181 if (skb == NULL) 182 goto errout; 183 184 err = br_fill_ifinfo(skb, port, 0, 0, event, 0, 0, port->dev); 185 if (err < 0) { 186 /* -EMSGSIZE implies BUG in br_nlmsg_size() */ 187 WARN_ON(err == -EMSGSIZE); 188 kfree_skb(skb); 189 goto errout; 190 } 191 rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC); 192 return; 193 errout: 194 if (err < 0) 195 rtnl_set_sk_err(net, RTNLGRP_LINK, err); 196 } 197 198 199 /* 200 * Dump information about all ports, in response to GETLINK 201 */ 202 int br_getlink(struct sk_buff *skb, u32 pid, u32 seq, 203 struct net_device *dev, u32 filter_mask) 204 { 205 int err = 0; 206 struct net_bridge_port *port = br_port_get_rcu(dev); 207 208 /* not a bridge port and */ 209 if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN)) 210 goto out; 211 212 err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI, 213 filter_mask, dev); 214 out: 215 return err; 216 } 217 218 static const struct nla_policy ifla_br_policy[IFLA_MAX+1] = { 219 [IFLA_BRIDGE_FLAGS] = { .type = NLA_U16 }, 220 [IFLA_BRIDGE_MODE] = { .type = NLA_U16 }, 221 [IFLA_BRIDGE_VLAN_INFO] = { .type = NLA_BINARY, 222 .len = sizeof(struct bridge_vlan_info), }, 223 }; 224 225 static int br_afspec(struct net_bridge *br, 226 struct net_bridge_port *p, 227 struct nlattr *af_spec, 228 int cmd) 229 { 230 struct nlattr *tb[IFLA_BRIDGE_MAX+1]; 231 int err = 0; 232 233 err = nla_parse_nested(tb, IFLA_BRIDGE_MAX, af_spec, ifla_br_policy); 234 if (err) 235 return err; 236 237 if (tb[IFLA_BRIDGE_VLAN_INFO]) { 238 struct bridge_vlan_info *vinfo; 239 240 vinfo = nla_data(tb[IFLA_BRIDGE_VLAN_INFO]); 241 242 if (vinfo->vid >= VLAN_N_VID) 243 return -EINVAL; 244 245 switch (cmd) { 246 case RTM_SETLINK: 247 if (p) { 248 err = nbp_vlan_add(p, vinfo->vid, vinfo->flags); 249 if (err) 250 break; 251 252 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 253 err = br_vlan_add(p->br, vinfo->vid, 254 vinfo->flags); 255 } else 256 err = br_vlan_add(br, vinfo->vid, vinfo->flags); 257 258 if (err) 259 break; 260 261 break; 262 263 case RTM_DELLINK: 264 if (p) { 265 nbp_vlan_delete(p, vinfo->vid); 266 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 267 br_vlan_delete(p->br, vinfo->vid); 268 } else 269 br_vlan_delete(br, vinfo->vid); 270 break; 271 } 272 } 273 274 return err; 275 } 276 277 static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = { 278 [IFLA_BRPORT_STATE] = { .type = NLA_U8 }, 279 [IFLA_BRPORT_COST] = { .type = NLA_U32 }, 280 [IFLA_BRPORT_PRIORITY] = { .type = NLA_U16 }, 281 [IFLA_BRPORT_MODE] = { .type = NLA_U8 }, 282 [IFLA_BRPORT_GUARD] = { .type = NLA_U8 }, 283 [IFLA_BRPORT_PROTECT] = { .type = NLA_U8 }, 284 }; 285 286 /* Change the state of the port and notify spanning tree */ 287 static int br_set_port_state(struct net_bridge_port *p, u8 state) 288 { 289 if (state > BR_STATE_BLOCKING) 290 return -EINVAL; 291 292 /* if kernel STP is running, don't allow changes */ 293 if (p->br->stp_enabled == BR_KERNEL_STP) 294 return -EBUSY; 295 296 /* if device is not up, change is not allowed 297 * if link is not present, only allowable state is disabled 298 */ 299 if (!netif_running(p->dev) || 300 (!netif_oper_up(p->dev) && state != BR_STATE_DISABLED)) 301 return -ENETDOWN; 302 303 p->state = state; 304 br_log_state(p); 305 br_port_state_selection(p->br); 306 return 0; 307 } 308 309 /* Set/clear or port flags based on attribute */ 310 static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[], 311 int attrtype, unsigned long mask) 312 { 313 if (tb[attrtype]) { 314 u8 flag = nla_get_u8(tb[attrtype]); 315 if (flag) 316 p->flags |= mask; 317 else 318 p->flags &= ~mask; 319 } 320 } 321 322 /* Process bridge protocol info on port */ 323 static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) 324 { 325 int err; 326 327 br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE); 328 br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD); 329 br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE); 330 br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK); 331 332 if (tb[IFLA_BRPORT_COST]) { 333 err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST])); 334 if (err) 335 return err; 336 } 337 338 if (tb[IFLA_BRPORT_PRIORITY]) { 339 err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY])); 340 if (err) 341 return err; 342 } 343 344 if (tb[IFLA_BRPORT_STATE]) { 345 err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE])); 346 if (err) 347 return err; 348 } 349 return 0; 350 } 351 352 /* Change state and parameters on port. */ 353 int br_setlink(struct net_device *dev, struct nlmsghdr *nlh) 354 { 355 struct nlattr *protinfo; 356 struct nlattr *afspec; 357 struct net_bridge_port *p; 358 struct nlattr *tb[IFLA_BRPORT_MAX + 1]; 359 int err = 0; 360 361 protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_PROTINFO); 362 afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC); 363 if (!protinfo && !afspec) 364 return 0; 365 366 p = br_port_get_rtnl(dev); 367 /* We want to accept dev as bridge itself if the AF_SPEC 368 * is set to see if someone is setting vlan info on the brigde 369 */ 370 if (!p && !afspec) 371 return -EINVAL; 372 373 if (p && protinfo) { 374 if (protinfo->nla_type & NLA_F_NESTED) { 375 err = nla_parse_nested(tb, IFLA_BRPORT_MAX, 376 protinfo, ifla_brport_policy); 377 if (err) 378 return err; 379 380 spin_lock_bh(&p->br->lock); 381 err = br_setport(p, tb); 382 spin_unlock_bh(&p->br->lock); 383 } else { 384 /* Binary compatability with old RSTP */ 385 if (nla_len(protinfo) < sizeof(u8)) 386 return -EINVAL; 387 388 spin_lock_bh(&p->br->lock); 389 err = br_set_port_state(p, nla_get_u8(protinfo)); 390 spin_unlock_bh(&p->br->lock); 391 } 392 if (err) 393 goto out; 394 } 395 396 if (afspec) { 397 err = br_afspec((struct net_bridge *)netdev_priv(dev), p, 398 afspec, RTM_SETLINK); 399 } 400 401 if (err == 0) 402 br_ifinfo_notify(RTM_NEWLINK, p); 403 404 out: 405 return err; 406 } 407 408 /* Delete port information */ 409 int br_dellink(struct net_device *dev, struct nlmsghdr *nlh) 410 { 411 struct nlattr *afspec; 412 struct net_bridge_port *p; 413 int err; 414 415 afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC); 416 if (!afspec) 417 return 0; 418 419 p = br_port_get_rtnl(dev); 420 /* We want to accept dev as bridge itself as well */ 421 if (!p && !(dev->priv_flags & IFF_EBRIDGE)) 422 return -EINVAL; 423 424 err = br_afspec((struct net_bridge *)netdev_priv(dev), p, 425 afspec, RTM_DELLINK); 426 427 return err; 428 } 429 static int br_validate(struct nlattr *tb[], struct nlattr *data[]) 430 { 431 if (tb[IFLA_ADDRESS]) { 432 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 433 return -EINVAL; 434 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 435 return -EADDRNOTAVAIL; 436 } 437 438 return 0; 439 } 440 441 static size_t br_get_link_af_size(const struct net_device *dev) 442 { 443 struct net_port_vlans *pv; 444 445 if (br_port_exists(dev)) 446 pv = nbp_get_vlan_info(br_port_get_rcu(dev)); 447 else if (dev->priv_flags & IFF_EBRIDGE) 448 pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev)); 449 else 450 return 0; 451 452 if (!pv) 453 return 0; 454 455 /* Each VLAN is returned in bridge_vlan_info along with flags */ 456 return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info)); 457 } 458 459 static struct rtnl_af_ops br_af_ops = { 460 .family = AF_BRIDGE, 461 .get_link_af_size = br_get_link_af_size, 462 }; 463 464 struct rtnl_link_ops br_link_ops __read_mostly = { 465 .kind = "bridge", 466 .priv_size = sizeof(struct net_bridge), 467 .setup = br_dev_setup, 468 .validate = br_validate, 469 .dellink = br_dev_delete, 470 }; 471 472 int __init br_netlink_init(void) 473 { 474 int err; 475 476 br_mdb_init(); 477 err = rtnl_af_register(&br_af_ops); 478 if (err) 479 goto out; 480 481 err = rtnl_link_register(&br_link_ops); 482 if (err) 483 goto out_af; 484 485 return 0; 486 487 out_af: 488 rtnl_af_unregister(&br_af_ops); 489 out: 490 br_mdb_uninit(); 491 return err; 492 } 493 494 void __exit br_netlink_fini(void) 495 { 496 br_mdb_uninit(); 497 rtnl_af_unregister(&br_af_ops); 498 rtnl_link_unregister(&br_link_ops); 499 } 500