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 + nla_total_size(1) /* IFLA_BRPORT_LEARNING */ 34 + nla_total_size(1) /* IFLA_BRPORT_UNICAST_FLOOD */ 35 + 0; 36 } 37 38 static inline size_t br_nlmsg_size(void) 39 { 40 return NLMSG_ALIGN(sizeof(struct ifinfomsg)) 41 + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */ 42 + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */ 43 + nla_total_size(4) /* IFLA_MASTER */ 44 + nla_total_size(4) /* IFLA_MTU */ 45 + nla_total_size(4) /* IFLA_LINK */ 46 + nla_total_size(1) /* IFLA_OPERSTATE */ 47 + nla_total_size(br_port_info_size()); /* IFLA_PROTINFO */ 48 } 49 50 static int br_port_fill_attrs(struct sk_buff *skb, 51 const struct net_bridge_port *p) 52 { 53 u8 mode = !!(p->flags & BR_HAIRPIN_MODE); 54 55 if (nla_put_u8(skb, IFLA_BRPORT_STATE, p->state) || 56 nla_put_u16(skb, IFLA_BRPORT_PRIORITY, p->priority) || 57 nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) || 58 nla_put_u8(skb, IFLA_BRPORT_MODE, mode) || 59 nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) || 60 nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) || 61 nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE)) || 62 nla_put_u8(skb, IFLA_BRPORT_LEARNING, !!(p->flags & BR_LEARNING)) || 63 nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD, !!(p->flags & BR_FLOOD))) 64 return -EMSGSIZE; 65 66 return 0; 67 } 68 69 /* 70 * Create one netlink message for one interface 71 * Contains port and master info as well as carrier and bridge state. 72 */ 73 static int br_fill_ifinfo(struct sk_buff *skb, 74 const struct net_bridge_port *port, 75 u32 pid, u32 seq, int event, unsigned int flags, 76 u32 filter_mask, const struct net_device *dev) 77 { 78 const struct net_bridge *br; 79 struct ifinfomsg *hdr; 80 struct nlmsghdr *nlh; 81 u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN; 82 83 if (port) 84 br = port->br; 85 else 86 br = netdev_priv(dev); 87 88 br_debug(br, "br_fill_info event %d port %s master %s\n", 89 event, dev->name, br->dev->name); 90 91 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags); 92 if (nlh == NULL) 93 return -EMSGSIZE; 94 95 hdr = nlmsg_data(nlh); 96 hdr->ifi_family = AF_BRIDGE; 97 hdr->__ifi_pad = 0; 98 hdr->ifi_type = dev->type; 99 hdr->ifi_index = dev->ifindex; 100 hdr->ifi_flags = dev_get_flags(dev); 101 hdr->ifi_change = 0; 102 103 if (nla_put_string(skb, IFLA_IFNAME, dev->name) || 104 nla_put_u32(skb, IFLA_MASTER, br->dev->ifindex) || 105 nla_put_u32(skb, IFLA_MTU, dev->mtu) || 106 nla_put_u8(skb, IFLA_OPERSTATE, operstate) || 107 (dev->addr_len && 108 nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) || 109 (dev->ifindex != dev->iflink && 110 nla_put_u32(skb, IFLA_LINK, dev->iflink))) 111 goto nla_put_failure; 112 113 if (event == RTM_NEWLINK && port) { 114 struct nlattr *nest 115 = nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED); 116 117 if (nest == NULL || br_port_fill_attrs(skb, port) < 0) 118 goto nla_put_failure; 119 nla_nest_end(skb, nest); 120 } 121 122 /* Check if the VID information is requested */ 123 if (filter_mask & RTEXT_FILTER_BRVLAN) { 124 struct nlattr *af; 125 const struct net_port_vlans *pv; 126 struct bridge_vlan_info vinfo; 127 u16 vid; 128 u16 pvid; 129 130 if (port) 131 pv = nbp_get_vlan_info(port); 132 else 133 pv = br_get_vlan_info(br); 134 135 if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID)) 136 goto done; 137 138 af = nla_nest_start(skb, IFLA_AF_SPEC); 139 if (!af) 140 goto nla_put_failure; 141 142 pvid = br_get_pvid(pv); 143 for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) { 144 vinfo.vid = vid; 145 vinfo.flags = 0; 146 if (vid == pvid) 147 vinfo.flags |= BRIDGE_VLAN_INFO_PVID; 148 149 if (test_bit(vid, pv->untagged_bitmap)) 150 vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED; 151 152 if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO, 153 sizeof(vinfo), &vinfo)) 154 goto nla_put_failure; 155 } 156 157 nla_nest_end(skb, af); 158 } 159 160 done: 161 return nlmsg_end(skb, nlh); 162 163 nla_put_failure: 164 nlmsg_cancel(skb, nlh); 165 return -EMSGSIZE; 166 } 167 168 /* 169 * Notify listeners of a change in port information 170 */ 171 void br_ifinfo_notify(int event, struct net_bridge_port *port) 172 { 173 struct net *net; 174 struct sk_buff *skb; 175 int err = -ENOBUFS; 176 177 if (!port) 178 return; 179 180 net = dev_net(port->dev); 181 br_debug(port->br, "port %u(%s) event %d\n", 182 (unsigned int)port->port_no, port->dev->name, event); 183 184 skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC); 185 if (skb == NULL) 186 goto errout; 187 188 err = br_fill_ifinfo(skb, port, 0, 0, event, 0, 0, port->dev); 189 if (err < 0) { 190 /* -EMSGSIZE implies BUG in br_nlmsg_size() */ 191 WARN_ON(err == -EMSGSIZE); 192 kfree_skb(skb); 193 goto errout; 194 } 195 rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC); 196 return; 197 errout: 198 rtnl_set_sk_err(net, RTNLGRP_LINK, err); 199 } 200 201 202 /* 203 * Dump information about all ports, in response to GETLINK 204 */ 205 int br_getlink(struct sk_buff *skb, u32 pid, u32 seq, 206 struct net_device *dev, u32 filter_mask) 207 { 208 int err = 0; 209 struct net_bridge_port *port = br_port_get_rtnl(dev); 210 211 if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN)) 212 goto out; 213 214 err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI, 215 filter_mask, dev); 216 out: 217 return err; 218 } 219 220 static const struct nla_policy ifla_br_policy[IFLA_MAX+1] = { 221 [IFLA_BRIDGE_FLAGS] = { .type = NLA_U16 }, 222 [IFLA_BRIDGE_MODE] = { .type = NLA_U16 }, 223 [IFLA_BRIDGE_VLAN_INFO] = { .type = NLA_BINARY, 224 .len = sizeof(struct bridge_vlan_info), }, 225 }; 226 227 static int br_afspec(struct net_bridge *br, 228 struct net_bridge_port *p, 229 struct nlattr *af_spec, 230 int cmd) 231 { 232 struct nlattr *tb[IFLA_BRIDGE_MAX+1]; 233 int err = 0; 234 235 err = nla_parse_nested(tb, IFLA_BRIDGE_MAX, af_spec, ifla_br_policy); 236 if (err) 237 return err; 238 239 if (tb[IFLA_BRIDGE_VLAN_INFO]) { 240 struct bridge_vlan_info *vinfo; 241 242 vinfo = nla_data(tb[IFLA_BRIDGE_VLAN_INFO]); 243 244 if (!vinfo->vid || vinfo->vid >= VLAN_VID_MASK) 245 return -EINVAL; 246 247 switch (cmd) { 248 case RTM_SETLINK: 249 if (p) { 250 err = nbp_vlan_add(p, vinfo->vid, vinfo->flags); 251 if (err) 252 break; 253 254 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 255 err = br_vlan_add(p->br, vinfo->vid, 256 vinfo->flags); 257 } else 258 err = br_vlan_add(br, vinfo->vid, vinfo->flags); 259 260 if (err) 261 break; 262 263 break; 264 265 case RTM_DELLINK: 266 if (p) { 267 nbp_vlan_delete(p, vinfo->vid); 268 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 269 br_vlan_delete(p->br, vinfo->vid); 270 } else 271 br_vlan_delete(br, vinfo->vid); 272 break; 273 } 274 } 275 276 return err; 277 } 278 279 static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = { 280 [IFLA_BRPORT_STATE] = { .type = NLA_U8 }, 281 [IFLA_BRPORT_COST] = { .type = NLA_U32 }, 282 [IFLA_BRPORT_PRIORITY] = { .type = NLA_U16 }, 283 [IFLA_BRPORT_MODE] = { .type = NLA_U8 }, 284 [IFLA_BRPORT_GUARD] = { .type = NLA_U8 }, 285 [IFLA_BRPORT_PROTECT] = { .type = NLA_U8 }, 286 [IFLA_BRPORT_LEARNING] = { .type = NLA_U8 }, 287 [IFLA_BRPORT_UNICAST_FLOOD] = { .type = NLA_U8 }, 288 }; 289 290 /* Change the state of the port and notify spanning tree */ 291 static int br_set_port_state(struct net_bridge_port *p, u8 state) 292 { 293 if (state > BR_STATE_BLOCKING) 294 return -EINVAL; 295 296 /* if kernel STP is running, don't allow changes */ 297 if (p->br->stp_enabled == BR_KERNEL_STP) 298 return -EBUSY; 299 300 /* if device is not up, change is not allowed 301 * if link is not present, only allowable state is disabled 302 */ 303 if (!netif_running(p->dev) || 304 (!netif_oper_up(p->dev) && state != BR_STATE_DISABLED)) 305 return -ENETDOWN; 306 307 p->state = state; 308 br_log_state(p); 309 br_port_state_selection(p->br); 310 return 0; 311 } 312 313 /* Set/clear or port flags based on attribute */ 314 static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[], 315 int attrtype, unsigned long mask) 316 { 317 if (tb[attrtype]) { 318 u8 flag = nla_get_u8(tb[attrtype]); 319 if (flag) 320 p->flags |= mask; 321 else 322 p->flags &= ~mask; 323 } 324 } 325 326 /* Process bridge protocol info on port */ 327 static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) 328 { 329 int err; 330 unsigned long old_flags = p->flags; 331 332 br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE); 333 br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD); 334 br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE); 335 br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK); 336 br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING); 337 br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD); 338 339 if (tb[IFLA_BRPORT_COST]) { 340 err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST])); 341 if (err) 342 return err; 343 } 344 345 if (tb[IFLA_BRPORT_PRIORITY]) { 346 err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY])); 347 if (err) 348 return err; 349 } 350 351 if (tb[IFLA_BRPORT_STATE]) { 352 err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE])); 353 if (err) 354 return err; 355 } 356 357 br_port_flags_change(p, old_flags ^ p->flags); 358 return 0; 359 } 360 361 /* Change state and parameters on port. */ 362 int br_setlink(struct net_device *dev, struct nlmsghdr *nlh) 363 { 364 struct nlattr *protinfo; 365 struct nlattr *afspec; 366 struct net_bridge_port *p; 367 struct nlattr *tb[IFLA_BRPORT_MAX + 1]; 368 int err = 0; 369 370 protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_PROTINFO); 371 afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC); 372 if (!protinfo && !afspec) 373 return 0; 374 375 p = br_port_get_rtnl(dev); 376 /* We want to accept dev as bridge itself if the AF_SPEC 377 * is set to see if someone is setting vlan info on the bridge 378 */ 379 if (!p && !afspec) 380 return -EINVAL; 381 382 if (p && protinfo) { 383 if (protinfo->nla_type & NLA_F_NESTED) { 384 err = nla_parse_nested(tb, IFLA_BRPORT_MAX, 385 protinfo, ifla_brport_policy); 386 if (err) 387 return err; 388 389 spin_lock_bh(&p->br->lock); 390 err = br_setport(p, tb); 391 spin_unlock_bh(&p->br->lock); 392 } else { 393 /* Binary compatibility with old RSTP */ 394 if (nla_len(protinfo) < sizeof(u8)) 395 return -EINVAL; 396 397 spin_lock_bh(&p->br->lock); 398 err = br_set_port_state(p, nla_get_u8(protinfo)); 399 spin_unlock_bh(&p->br->lock); 400 } 401 if (err) 402 goto out; 403 } 404 405 if (afspec) { 406 err = br_afspec((struct net_bridge *)netdev_priv(dev), p, 407 afspec, RTM_SETLINK); 408 } 409 410 if (err == 0) 411 br_ifinfo_notify(RTM_NEWLINK, p); 412 413 out: 414 return err; 415 } 416 417 /* Delete port information */ 418 int br_dellink(struct net_device *dev, struct nlmsghdr *nlh) 419 { 420 struct nlattr *afspec; 421 struct net_bridge_port *p; 422 int err; 423 424 afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC); 425 if (!afspec) 426 return 0; 427 428 p = br_port_get_rtnl(dev); 429 /* We want to accept dev as bridge itself as well */ 430 if (!p && !(dev->priv_flags & IFF_EBRIDGE)) 431 return -EINVAL; 432 433 err = br_afspec((struct net_bridge *)netdev_priv(dev), p, 434 afspec, RTM_DELLINK); 435 436 return err; 437 } 438 static int br_validate(struct nlattr *tb[], struct nlattr *data[]) 439 { 440 if (tb[IFLA_ADDRESS]) { 441 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 442 return -EINVAL; 443 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 444 return -EADDRNOTAVAIL; 445 } 446 447 return 0; 448 } 449 450 static int br_dev_newlink(struct net *src_net, struct net_device *dev, 451 struct nlattr *tb[], struct nlattr *data[]) 452 { 453 struct net_bridge *br = netdev_priv(dev); 454 455 if (tb[IFLA_ADDRESS]) { 456 spin_lock_bh(&br->lock); 457 br_stp_change_bridge_id(br, nla_data(tb[IFLA_ADDRESS])); 458 spin_unlock_bh(&br->lock); 459 } 460 461 return register_netdevice(dev); 462 } 463 464 static size_t br_get_link_af_size(const struct net_device *dev) 465 { 466 struct net_port_vlans *pv; 467 468 if (br_port_exists(dev)) 469 pv = nbp_get_vlan_info(br_port_get_rtnl(dev)); 470 else if (dev->priv_flags & IFF_EBRIDGE) 471 pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev)); 472 else 473 return 0; 474 475 if (!pv) 476 return 0; 477 478 /* Each VLAN is returned in bridge_vlan_info along with flags */ 479 return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info)); 480 } 481 482 static struct rtnl_af_ops br_af_ops = { 483 .family = AF_BRIDGE, 484 .get_link_af_size = br_get_link_af_size, 485 }; 486 487 struct rtnl_link_ops br_link_ops __read_mostly = { 488 .kind = "bridge", 489 .priv_size = sizeof(struct net_bridge), 490 .setup = br_dev_setup, 491 .validate = br_validate, 492 .newlink = br_dev_newlink, 493 .dellink = br_dev_delete, 494 }; 495 496 int __init br_netlink_init(void) 497 { 498 int err; 499 500 br_mdb_init(); 501 rtnl_af_register(&br_af_ops); 502 503 err = rtnl_link_register(&br_link_ops); 504 if (err) 505 goto out_af; 506 507 return 0; 508 509 out_af: 510 rtnl_af_unregister(&br_af_ops); 511 br_mdb_uninit(); 512 return err; 513 } 514 515 void __exit br_netlink_fini(void) 516 { 517 br_mdb_uninit(); 518 rtnl_af_unregister(&br_af_ops); 519 rtnl_link_unregister(&br_link_ops); 520 } 521