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 (vid = find_first_bit(pv->vlan_bitmap, BR_VLAN_BITMAP_LEN); 140 vid < BR_VLAN_BITMAP_LEN; 141 vid = find_next_bit(pv->vlan_bitmap, 142 BR_VLAN_BITMAP_LEN, vid+1)) { 143 vinfo.vid = vid; 144 vinfo.flags = 0; 145 if (vid == pvid) 146 vinfo.flags |= BRIDGE_VLAN_INFO_PVID; 147 148 if (test_bit(vid, pv->untagged_bitmap)) 149 vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED; 150 151 if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO, 152 sizeof(vinfo), &vinfo)) 153 goto nla_put_failure; 154 } 155 156 nla_nest_end(skb, af); 157 } 158 159 done: 160 return nlmsg_end(skb, nlh); 161 162 nla_put_failure: 163 nlmsg_cancel(skb, nlh); 164 return -EMSGSIZE; 165 } 166 167 /* 168 * Notify listeners of a change in port information 169 */ 170 void br_ifinfo_notify(int event, struct net_bridge_port *port) 171 { 172 struct net *net; 173 struct sk_buff *skb; 174 int err = -ENOBUFS; 175 176 if (!port) 177 return; 178 179 net = dev_net(port->dev); 180 br_debug(port->br, "port %u(%s) event %d\n", 181 (unsigned int)port->port_no, port->dev->name, event); 182 183 skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC); 184 if (skb == NULL) 185 goto errout; 186 187 err = br_fill_ifinfo(skb, port, 0, 0, event, 0, 0, port->dev); 188 if (err < 0) { 189 /* -EMSGSIZE implies BUG in br_nlmsg_size() */ 190 WARN_ON(err == -EMSGSIZE); 191 kfree_skb(skb); 192 goto errout; 193 } 194 rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC); 195 return; 196 errout: 197 if (err < 0) 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_rcu(dev); 210 211 /* not a bridge port and */ 212 if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN)) 213 goto out; 214 215 err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI, 216 filter_mask, dev); 217 out: 218 return err; 219 } 220 221 static const struct nla_policy ifla_br_policy[IFLA_MAX+1] = { 222 [IFLA_BRIDGE_FLAGS] = { .type = NLA_U16 }, 223 [IFLA_BRIDGE_MODE] = { .type = NLA_U16 }, 224 [IFLA_BRIDGE_VLAN_INFO] = { .type = NLA_BINARY, 225 .len = sizeof(struct bridge_vlan_info), }, 226 }; 227 228 static int br_afspec(struct net_bridge *br, 229 struct net_bridge_port *p, 230 struct nlattr *af_spec, 231 int cmd) 232 { 233 struct nlattr *tb[IFLA_BRIDGE_MAX+1]; 234 int err = 0; 235 236 err = nla_parse_nested(tb, IFLA_BRIDGE_MAX, af_spec, ifla_br_policy); 237 if (err) 238 return err; 239 240 if (tb[IFLA_BRIDGE_VLAN_INFO]) { 241 struct bridge_vlan_info *vinfo; 242 243 vinfo = nla_data(tb[IFLA_BRIDGE_VLAN_INFO]); 244 245 if (vinfo->vid >= VLAN_N_VID) 246 return -EINVAL; 247 248 switch (cmd) { 249 case RTM_SETLINK: 250 if (p) { 251 err = nbp_vlan_add(p, vinfo->vid, vinfo->flags); 252 if (err) 253 break; 254 255 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 256 err = br_vlan_add(p->br, vinfo->vid, 257 vinfo->flags); 258 } else 259 err = br_vlan_add(br, vinfo->vid, vinfo->flags); 260 261 if (err) 262 break; 263 264 break; 265 266 case RTM_DELLINK: 267 if (p) { 268 nbp_vlan_delete(p, vinfo->vid); 269 if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER) 270 br_vlan_delete(p->br, vinfo->vid); 271 } else 272 br_vlan_delete(br, vinfo->vid); 273 break; 274 } 275 } 276 277 return err; 278 } 279 280 static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = { 281 [IFLA_BRPORT_STATE] = { .type = NLA_U8 }, 282 [IFLA_BRPORT_COST] = { .type = NLA_U32 }, 283 [IFLA_BRPORT_PRIORITY] = { .type = NLA_U16 }, 284 [IFLA_BRPORT_MODE] = { .type = NLA_U8 }, 285 [IFLA_BRPORT_GUARD] = { .type = NLA_U8 }, 286 [IFLA_BRPORT_PROTECT] = { .type = NLA_U8 }, 287 }; 288 289 /* Change the state of the port and notify spanning tree */ 290 static int br_set_port_state(struct net_bridge_port *p, u8 state) 291 { 292 if (state > BR_STATE_BLOCKING) 293 return -EINVAL; 294 295 /* if kernel STP is running, don't allow changes */ 296 if (p->br->stp_enabled == BR_KERNEL_STP) 297 return -EBUSY; 298 299 /* if device is not up, change is not allowed 300 * if link is not present, only allowable state is disabled 301 */ 302 if (!netif_running(p->dev) || 303 (!netif_oper_up(p->dev) && state != BR_STATE_DISABLED)) 304 return -ENETDOWN; 305 306 p->state = state; 307 br_log_state(p); 308 br_port_state_selection(p->br); 309 return 0; 310 } 311 312 /* Set/clear or port flags based on attribute */ 313 static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[], 314 int attrtype, unsigned long mask) 315 { 316 if (tb[attrtype]) { 317 u8 flag = nla_get_u8(tb[attrtype]); 318 if (flag) 319 p->flags |= mask; 320 else 321 p->flags &= ~mask; 322 } 323 } 324 325 /* Process bridge protocol info on port */ 326 static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) 327 { 328 int err; 329 330 br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE); 331 br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD); 332 br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE); 333 br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK); 334 335 if (tb[IFLA_BRPORT_COST]) { 336 err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST])); 337 if (err) 338 return err; 339 } 340 341 if (tb[IFLA_BRPORT_PRIORITY]) { 342 err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY])); 343 if (err) 344 return err; 345 } 346 347 if (tb[IFLA_BRPORT_STATE]) { 348 err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE])); 349 if (err) 350 return err; 351 } 352 return 0; 353 } 354 355 /* Change state and parameters on port. */ 356 int br_setlink(struct net_device *dev, struct nlmsghdr *nlh) 357 { 358 struct ifinfomsg *ifm; 359 struct nlattr *protinfo; 360 struct nlattr *afspec; 361 struct net_bridge_port *p; 362 struct nlattr *tb[IFLA_BRPORT_MAX + 1]; 363 int err; 364 365 ifm = nlmsg_data(nlh); 366 367 protinfo = nlmsg_find_attr(nlh, sizeof(*ifm), IFLA_PROTINFO); 368 afspec = nlmsg_find_attr(nlh, sizeof(*ifm), IFLA_AF_SPEC); 369 if (!protinfo && !afspec) 370 return 0; 371 372 p = br_port_get_rtnl(dev); 373 /* We want to accept dev as bridge itself if the AF_SPEC 374 * is set to see if someone is setting vlan info on the brigde 375 */ 376 if (!p && ((dev->priv_flags & IFF_EBRIDGE) && !afspec)) 377 return -EINVAL; 378 379 if (p && protinfo) { 380 if (protinfo->nla_type & NLA_F_NESTED) { 381 err = nla_parse_nested(tb, IFLA_BRPORT_MAX, 382 protinfo, ifla_brport_policy); 383 if (err) 384 return err; 385 386 spin_lock_bh(&p->br->lock); 387 err = br_setport(p, tb); 388 spin_unlock_bh(&p->br->lock); 389 } else { 390 /* Binary compatability with old RSTP */ 391 if (nla_len(protinfo) < sizeof(u8)) 392 return -EINVAL; 393 394 spin_lock_bh(&p->br->lock); 395 err = br_set_port_state(p, nla_get_u8(protinfo)); 396 spin_unlock_bh(&p->br->lock); 397 } 398 if (err) 399 goto out; 400 } 401 402 if (afspec) { 403 err = br_afspec((struct net_bridge *)netdev_priv(dev), p, 404 afspec, RTM_SETLINK); 405 } 406 407 if (err == 0) 408 br_ifinfo_notify(RTM_NEWLINK, p); 409 410 out: 411 return err; 412 } 413 414 /* Delete port information */ 415 int br_dellink(struct net_device *dev, struct nlmsghdr *nlh) 416 { 417 struct ifinfomsg *ifm; 418 struct nlattr *afspec; 419 struct net_bridge_port *p; 420 int err; 421 422 ifm = nlmsg_data(nlh); 423 424 afspec = nlmsg_find_attr(nlh, sizeof(*ifm), 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 size_t br_get_link_af_size(const struct net_device *dev) 451 { 452 struct net_port_vlans *pv; 453 454 if (br_port_exists(dev)) 455 pv = nbp_get_vlan_info(br_port_get_rcu(dev)); 456 else if (dev->priv_flags & IFF_EBRIDGE) 457 pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev)); 458 else 459 return 0; 460 461 if (!pv) 462 return 0; 463 464 /* Each VLAN is returned in bridge_vlan_info along with flags */ 465 return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info)); 466 } 467 468 static struct rtnl_af_ops br_af_ops = { 469 .family = AF_BRIDGE, 470 .get_link_af_size = br_get_link_af_size, 471 }; 472 473 struct rtnl_link_ops br_link_ops __read_mostly = { 474 .kind = "bridge", 475 .priv_size = sizeof(struct net_bridge), 476 .setup = br_dev_setup, 477 .validate = br_validate, 478 .dellink = br_dev_delete, 479 }; 480 481 int __init br_netlink_init(void) 482 { 483 int err; 484 485 br_mdb_init(); 486 err = rtnl_af_register(&br_af_ops); 487 if (err) 488 goto out; 489 490 err = rtnl_link_register(&br_link_ops); 491 if (err) 492 goto out_af; 493 494 return 0; 495 496 out_af: 497 rtnl_af_unregister(&br_af_ops); 498 out: 499 br_mdb_uninit(); 500 return err; 501 } 502 503 void __exit br_netlink_fini(void) 504 { 505 br_mdb_uninit(); 506 rtnl_af_unregister(&br_af_ops); 507 rtnl_link_unregister(&br_link_ops); 508 } 509