Pileus Git - ~andy/linux/blob - net/bridge/br_netlink.c

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