net/core/rtnetlink.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Routing netlink socket interface: protocol independent part.
   7  *
   8  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   9  *
  10  *              This program is free software; you can redistribute it and/or
  11  *              modify it under the terms of the GNU General Public License
  12  *              as published by the Free Software Foundation; either version
  13  *              2 of the License, or (at your option) any later version.
  14  *
  15  *      Fixes:
  16  *      Vitaly E. Lavrov                RTA_OK arithmetics was wrong.
  17  */
  18
  19 #include <linux/errno.h>
  20 #include <linux/module.h>
  21 #include <linux/types.h>
  22 #include <linux/socket.h>
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/timer.h>
  26 #include <linux/string.h>
  27 #include <linux/sockios.h>
  28 #include <linux/net.h>
  29 #include <linux/fcntl.h>
  30 #include <linux/mm.h>
  31 #include <linux/slab.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/capability.h>
  34 #include <linux/skbuff.h>
  35 #include <linux/init.h>
  36 #include <linux/security.h>
  37 #include <linux/mutex.h>
  38 #include <linux/if_addr.h>
  39 #include <linux/vs_context.h> /* remove with NXF_HIDE_NETIF */
  40
  41 #include <asm/uaccess.h>
  42 #include <asm/system.h>
  43 #include <asm/string.h>
  44
  45 #include <linux/inet.h>
  46 #include <linux/netdevice.h>
  47 #include <net/ip.h>
  48 #include <net/protocol.h>
  49 #include <net/arp.h>
  50 #include <net/route.h>
  51 #include <net/udp.h>
  52 #include <net/sock.h>
  53 #include <net/pkt_sched.h>
  54 #include <net/fib_rules.h>
  55 #include <net/netlink.h>
  56 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
  57 #include <linux/wireless.h>
  58 #include <net/iw_handler.h>
  59 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
  60
  61 static DEFINE_MUTEX(rtnl_mutex);
  62 static struct sock *rtnl;
  63
  64 void rtnl_lock(void)
  65 {
  66         mutex_lock(&rtnl_mutex);
  67 }
  68
  69 void __rtnl_unlock(void)
  70 {
  71         mutex_unlock(&rtnl_mutex);
  72 }
  73
  74 void rtnl_unlock(void)
  75 {
  76         mutex_unlock(&rtnl_mutex);
  77         if (rtnl && rtnl->sk_receive_queue.qlen)
  78                 rtnl->sk_data_ready(rtnl, 0);
  79         netdev_run_todo();
  80 }
  81
  82 int rtnl_trylock(void)
  83 {
  84         return mutex_trylock(&rtnl_mutex);
  85 }
  86
  87 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
  88 {
  89         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
  90
  91         while (RTA_OK(rta, len)) {
  92                 unsigned flavor = rta->rta_type;
  93                 if (flavor && flavor <= maxattr)
  94                         tb[flavor-1] = rta;
  95                 rta = RTA_NEXT(rta, len);
  96         }
  97         return 0;
  98 }
  99
 100 struct rtnetlink_link * rtnetlink_links[NPROTO];
 101
 102 static const int rtm_min[RTM_NR_FAMILIES] =
 103 {
 104         [RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 105         [RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
 106         [RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
 107         [RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
 108         [RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
 109         [RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
 110         [RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
 111         [RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
 112         [RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 113         [RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 114 };
 115
 116 static const int rta_max[RTM_NR_FAMILIES] =
 117 {
 118         [RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
 119         [RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
 120         [RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
 121         [RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,
 122         [RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
 123         [RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
 124         [RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
 125         [RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
 126 };
 127
 128 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
 129 {
 130         struct rtattr *rta;
 131         int size = RTA_LENGTH(attrlen);
 132
 133         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
 134         rta->rta_type = attrtype;
 135         rta->rta_len = size;
 136         memcpy(RTA_DATA(rta), data, attrlen);
 137         memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
 138 }
 139
 140 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
 141 {
 142         size_t ret = RTA_PAYLOAD(rta);
 143         char *src = RTA_DATA(rta);
 144
 145         if (ret > 0 && src[ret - 1] == '\0')
 146                 ret--;
 147         if (size > 0) {
 148                 size_t len = (ret >= size) ? size - 1 : ret;
 149                 memset(dest, 0, size);
 150                 memcpy(dest, src, len);
 151         }
 152         return ret;
 153 }
 154
 155 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
 156 {
 157         int err = 0;
 158
 159         NETLINK_CB(skb).dst_group = group;
 160         if (echo)
 161                 atomic_inc(&skb->users);
 162         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
 163         if (echo)
 164                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 165         return err;
 166 }
 167
 168 int rtnl_unicast(struct sk_buff *skb, u32 pid)
 169 {
 170         return nlmsg_unicast(rtnl, skb, pid);
 171 }
 172
 173 int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
 174                 struct nlmsghdr *nlh, gfp_t flags)
 175 {
 176         int report = 0;
 177
 178         if (nlh)
 179                 report = nlmsg_report(nlh);
 180
 181         return nlmsg_notify(rtnl, skb, pid, group, report, flags);
 182 }
 183
 184 void rtnl_set_sk_err(u32 group, int error)
 185 {
 186         netlink_set_err(rtnl, 0, group, error);
 187 }
 188
 189 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
 190 {
 191         struct nlattr *mx;
 192         int i, valid = 0;
 193
 194         mx = nla_nest_start(skb, RTA_METRICS);
 195         if (mx == NULL)
 196                 return -ENOBUFS;
 197
 198         for (i = 0; i < RTAX_MAX; i++) {
 199                 if (metrics[i]) {
 200                         valid++;
 201                         NLA_PUT_U32(skb, i+1, metrics[i]);
 202                 }
 203         }
 204
 205         if (!valid) {
 206                 nla_nest_cancel(skb, mx);
 207                 return 0;
 208         }
 209
 210         return nla_nest_end(skb, mx);
 211
 212 nla_put_failure:
 213         return nla_nest_cancel(skb, mx);
 214 }
 215
 216 int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
 217                        u32 ts, u32 tsage, long expires, u32 error)
 218 {
 219         struct rta_cacheinfo ci = {
 220                 .rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
 221                 .rta_used = dst->__use,
 222                 .rta_clntref = atomic_read(&(dst->__refcnt)),
 223                 .rta_error = error,
 224                 .rta_id =  id,
 225                 .rta_ts = ts,
 226                 .rta_tsage = tsage,
 227         };
 228
 229         if (expires)
 230                 ci.rta_expires = jiffies_to_clock_t(expires);
 231
 232         return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
 233 }
 234
 235 EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);
 236
 237 static void set_operstate(struct net_device *dev, unsigned char transition)
 238 {
 239         unsigned char operstate = dev->operstate;
 240
 241         switch(transition) {
 242         case IF_OPER_UP:
 243                 if ((operstate == IF_OPER_DORMANT ||
 244                      operstate == IF_OPER_UNKNOWN) &&
 245                     !netif_dormant(dev))
 246                         operstate = IF_OPER_UP;
 247                 break;
 248
 249         case IF_OPER_DORMANT:
 250                 if (operstate == IF_OPER_UP ||
 251                     operstate == IF_OPER_UNKNOWN)
 252                         operstate = IF_OPER_DORMANT;
 253                 break;
 254         };
 255
 256         if (dev->operstate != operstate) {
 257                 write_lock_bh(&dev_base_lock);
 258                 dev->operstate = operstate;
 259                 write_unlock_bh(&dev_base_lock);
 260                 netdev_state_change(dev);
 261         }
 262 }
 263
 264 static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
 265                                  struct net_device_stats *b)
 266 {
 267         a->rx_packets = b->rx_packets;
 268         a->tx_packets = b->tx_packets;
 269         a->rx_bytes = b->rx_bytes;
 270         a->tx_bytes = b->tx_bytes;
 271         a->rx_errors = b->rx_errors;
 272         a->tx_errors = b->tx_errors;
 273         a->rx_dropped = b->rx_dropped;
 274         a->tx_dropped = b->tx_dropped;
 275
 276         a->multicast = b->multicast;
 277         a->collisions = b->collisions;
 278
 279         a->rx_length_errors = b->rx_length_errors;
 280         a->rx_over_errors = b->rx_over_errors;
 281         a->rx_crc_errors = b->rx_crc_errors;
 282         a->rx_frame_errors = b->rx_frame_errors;
 283         a->rx_fifo_errors = b->rx_fifo_errors;
 284         a->rx_missed_errors = b->rx_missed_errors;
 285
 286         a->tx_aborted_errors = b->tx_aborted_errors;
 287         a->tx_carrier_errors = b->tx_carrier_errors;
 288         a->tx_fifo_errors = b->tx_fifo_errors;
 289         a->tx_heartbeat_errors = b->tx_heartbeat_errors;
 290         a->tx_window_errors = b->tx_window_errors;
 291
 292         a->rx_compressed = b->rx_compressed;
 293         a->tx_compressed = b->tx_compressed;
 294 };
 295
 296 static inline size_t if_nlmsg_size(int iwbuflen)
 297 {
 298         return NLMSG_ALIGN(sizeof(struct ifinfomsg))
 299                + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
 300                + nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
 301                + nla_total_size(sizeof(struct rtnl_link_ifmap))
 302                + nla_total_size(sizeof(struct rtnl_link_stats))
 303                + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
 304                + nla_total_size(MAX_ADDR_LEN) /* IFLA_BROADCAST */
 305                + nla_total_size(4) /* IFLA_TXQLEN */
 306                + nla_total_size(4) /* IFLA_WEIGHT */
 307                + nla_total_size(4) /* IFLA_MTU */
 308                + nla_total_size(4) /* IFLA_LINK */
 309                + nla_total_size(4) /* IFLA_MASTER */
 310                + nla_total_size(1) /* IFLA_OPERSTATE */
 311                + nla_total_size(1) /* IFLA_LINKMODE */
 312                + nla_total_size(iwbuflen);
 313 }
 314
 315 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 316                             void *iwbuf, int iwbuflen, int type, u32 pid,
 317                             u32 seq, u32 change, unsigned int flags)
 318 {
 319         struct ifinfomsg *ifm;
 320         struct nlmsghdr *nlh;
 321
 322         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
 323         if (nlh == NULL)
 324                 return -ENOBUFS;
 325
 326         ifm = nlmsg_data(nlh);
 327         ifm->ifi_family = AF_UNSPEC;
 328         ifm->__ifi_pad = 0;
 329         ifm->ifi_type = dev->type;
 330         ifm->ifi_index = dev->ifindex;
 331         ifm->ifi_flags = dev_get_flags(dev);
 332         ifm->ifi_change = change;
 333
 334         NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
 335         NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
 336         NLA_PUT_U32(skb, IFLA_WEIGHT, dev->weight);
 337         NLA_PUT_U8(skb, IFLA_OPERSTATE,
 338                    netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
 339         NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
 340         NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
 341
 342         if (dev->ifindex != dev->iflink)
 343                 NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
 344
 345         if (dev->master)
 346                 NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
 347
 348         if (dev->qdisc_sleeping)
 349                 NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
 350
 351         if (1) {
 352                 struct rtnl_link_ifmap map = {
 353                         .mem_start   = dev->mem_start,
 354                         .mem_end     = dev->mem_end,
 355                         .base_addr   = dev->base_addr,
 356                         .irq         = dev->irq,
 357                         .dma         = dev->dma,
 358                         .port        = dev->if_port,
 359                 };
 360                 NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
 361         }
 362
 363         if (dev->addr_len) {
 364                 NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
 365                 NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
 366         }
 367
 368         if (dev->get_stats) {
 369                 struct net_device_stats *stats = dev->get_stats(dev);
 370                 if (stats) {
 371                         struct nlattr *attr;
 372
 373                         attr = nla_reserve(skb, IFLA_STATS,
 374                                            sizeof(struct rtnl_link_stats));
 375                         if (attr == NULL)
 376                                 goto nla_put_failure;
 377
 378                         copy_rtnl_link_stats(nla_data(attr), stats);
 379                 }
 380         }
 381
 382         if (iwbuf)
 383                 NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
 384
 385         return nlmsg_end(skb, nlh);
 386
 387 nla_put_failure:
 388         return nlmsg_cancel(skb, nlh);
 389 }
 390
 391 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 392 {
 393         int idx;
 394         int s_idx = cb->args[0];
 395         struct net_device *dev;
 396
 397         read_lock(&dev_base_lock);
 398         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
 399                 if (idx < s_idx)
 400                         continue;
 401                 if (vx_info_flags(skb->sk->sk_vx_info, VXF_HIDE_NETIF, 0) &&
 402                         !dev_in_nx_info(dev, skb->sk->sk_nx_info))
 403                         continue;
 404                 if (rtnl_fill_ifinfo(skb, dev, NULL, 0, RTM_NEWLINK,
 405                                      NETLINK_CB(cb->skb).pid,
 406                                      cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
 407                         break;
 408         }
 409         read_unlock(&dev_base_lock);
 410         cb->args[0] = idx;
 411
 412         return skb->len;
 413 }
 414
 415 static struct nla_policy ifla_policy[IFLA_MAX+1] __read_mostly = {
 416         [IFLA_IFNAME]           = { .type = NLA_STRING, .len = IFNAMSIZ-1 },
 417         [IFLA_MAP]              = { .len = sizeof(struct rtnl_link_ifmap) },
 418         [IFLA_MTU]              = { .type = NLA_U32 },
 419         [IFLA_TXQLEN]           = { .type = NLA_U32 },
 420         [IFLA_WEIGHT]           = { .type = NLA_U32 },
 421         [IFLA_OPERSTATE]        = { .type = NLA_U8 },
 422         [IFLA_LINKMODE]         = { .type = NLA_U8 },
 423 };
 424
 425 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 426 {
 427         struct ifinfomsg *ifm;
 428         struct net_device *dev;
 429         int err, send_addr_notify = 0, modified = 0;
 430         struct nlattr *tb[IFLA_MAX+1];
 431         char ifname[IFNAMSIZ];
 432
 433         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 434         if (err < 0)
 435                 goto errout;
 436
 437         if (tb[IFLA_IFNAME])
 438                 nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
 439         else
 440                 ifname[0] = '\0';
 441
 442         err = -EINVAL;
 443         ifm = nlmsg_data(nlh);
 444         if (ifm->ifi_index >= 0)
 445                 dev = dev_get_by_index(ifm->ifi_index);
 446         else if (tb[IFLA_IFNAME])
 447                 dev = dev_get_by_name(ifname);
 448         else
 449                 goto errout;
 450
 451         if (dev == NULL) {
 452                 err = -ENODEV;
 453                 goto errout;
 454         }
 455
 456         if (tb[IFLA_ADDRESS] &&
 457             nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
 458                 goto errout_dev;
 459
 460         if (tb[IFLA_BROADCAST] &&
 461             nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
 462                 goto errout_dev;
 463
 464         if (tb[IFLA_MAP]) {
 465                 struct rtnl_link_ifmap *u_map;
 466                 struct ifmap k_map;
 467
 468                 if (!dev->set_config) {
 469                         err = -EOPNOTSUPP;
 470                         goto errout_dev;
 471                 }
 472
 473                 if (!netif_device_present(dev)) {
 474                         err = -ENODEV;
 475                         goto errout_dev;
 476                 }
 477
 478                 u_map = nla_data(tb[IFLA_MAP]);
 479                 k_map.mem_start = (unsigned long) u_map->mem_start;
 480                 k_map.mem_end = (unsigned long) u_map->mem_end;
 481                 k_map.base_addr = (unsigned short) u_map->base_addr;
 482                 k_map.irq = (unsigned char) u_map->irq;
 483                 k_map.dma = (unsigned char) u_map->dma;
 484                 k_map.port = (unsigned char) u_map->port;
 485
 486                 err = dev->set_config(dev, &k_map);
 487                 if (err < 0)
 488                         goto errout_dev;
 489
 490                 modified = 1;
 491         }
 492
 493         if (tb[IFLA_ADDRESS]) {
 494                 struct sockaddr *sa;
 495                 int len;
 496
 497                 if (!dev->set_mac_address) {
 498                         err = -EOPNOTSUPP;
 499                         goto errout_dev;
 500                 }
 501
 502                 if (!netif_device_present(dev)) {
 503                         err = -ENODEV;
 504                         goto errout_dev;
 505                 }
 506
 507                 len = sizeof(sa_family_t) + dev->addr_len;
 508                 sa = kmalloc(len, GFP_KERNEL);
 509                 if (!sa) {
 510                         err = -ENOMEM;
 511                         goto errout_dev;
 512                 }
 513                 sa->sa_family = dev->type;
 514                 memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
 515                        dev->addr_len);
 516                 err = dev->set_mac_address(dev, sa);
 517                 kfree(sa);
 518                 if (err)
 519                         goto errout_dev;
 520                 send_addr_notify = 1;
 521                 modified = 1;
 522         }
 523
 524         if (tb[IFLA_MTU]) {
 525                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 526                 if (err < 0)
 527                         goto errout_dev;
 528                 modified = 1;
 529         }
 530
 531         /*
 532          * Interface selected by interface index but interface
 533          * name provided implies that a name change has been
 534          * requested.
 535          */
 536         if (ifm->ifi_index >= 0 && ifname[0]) {
 537                 err = dev_change_name(dev, ifname);
 538                 if (err < 0)
 539                         goto errout_dev;
 540                 modified = 1;
 541         }
 542
 543 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 544         if (tb[IFLA_WIRELESS]) {
 545                 /* Call Wireless Extensions.
 546                  * Various stuff checked in there... */
 547                 err = wireless_rtnetlink_set(dev, nla_data(tb[IFLA_WIRELESS]),
 548                                              nla_len(tb[IFLA_WIRELESS]));
 549                 if (err < 0)
 550                         goto errout_dev;
 551         }
 552 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 553
 554         if (tb[IFLA_BROADCAST]) {
 555                 nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
 556                 send_addr_notify = 1;
 557         }
 558
 559
 560         if (ifm->ifi_flags)
 561                 dev_change_flags(dev, ifm->ifi_flags);
 562
 563         if (tb[IFLA_TXQLEN])
 564                 dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
 565
 566         if (tb[IFLA_WEIGHT])
 567                 dev->weight = nla_get_u32(tb[IFLA_WEIGHT]);
 568
 569         if (tb[IFLA_OPERSTATE])
 570                 set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
 571
 572         if (tb[IFLA_LINKMODE]) {
 573                 write_lock_bh(&dev_base_lock);
 574                 dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
 575                 write_unlock_bh(&dev_base_lock);
 576         }
 577
 578         err = 0;
 579
 580 errout_dev:
 581         if (err < 0 && modified && net_ratelimit())
 582                 printk(KERN_WARNING "A link change request failed with "
 583                        "some changes comitted already. Interface %s may "
 584                        "have been left with an inconsistent configuration, "
 585                        "please check.\n", dev->name);
 586
 587         if (send_addr_notify)
 588                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 589
 590         dev_put(dev);
 591 errout:
 592         return err;
 593 }
 594
 595 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 596 {
 597         struct ifinfomsg *ifm;
 598         struct nlattr *tb[IFLA_MAX+1];
 599         struct net_device *dev = NULL;
 600         struct sk_buff *nskb;
 601         char *iw_buf = NULL, *iw = NULL;
 602         int iw_buf_len = 0;
 603         int err;
 604
 605         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 606         if (err < 0)
 607                 return err;
 608
 609         ifm = nlmsg_data(nlh);
 610         if (ifm->ifi_index >= 0) {
 611                 dev = dev_get_by_index(ifm->ifi_index);
 612                 if (dev == NULL)
 613                         return -ENODEV;
 614         } else
 615                 return -EINVAL;
 616
 617
 618 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 619         if (tb[IFLA_WIRELESS]) {
 620                 /* Call Wireless Extensions. We need to know the size before
 621                  * we can alloc. Various stuff checked in there... */
 622                 err = wireless_rtnetlink_get(dev, nla_data(tb[IFLA_WIRELESS]),
 623                                              nla_len(tb[IFLA_WIRELESS]),
 624                                              &iw_buf, &iw_buf_len);
 625                 if (err < 0)
 626                         goto errout;
 627
 628                 iw += IW_EV_POINT_OFF;
 629         }
 630 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 631
 632         nskb = nlmsg_new(if_nlmsg_size(iw_buf_len), GFP_KERNEL);
 633         if (nskb == NULL) {
 634                 err = -ENOBUFS;
 635                 goto errout;
 636         }
 637
 638         err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK,
 639                                NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0);
 640         /* failure impilies BUG in if_nlmsg_size or wireless_rtnetlink_get */
 641         BUG_ON(err < 0);
 642
 643         err = rtnl_unicast(nskb, NETLINK_CB(skb).pid);
 644 errout:
 645         kfree(iw_buf);
 646         dev_put(dev);
 647
 648         return err;
 649 }
 650
 651 static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 652 {
 653         int idx;
 654         int s_idx = cb->family;
 655
 656         if (s_idx == 0)
 657                 s_idx = 1;
 658         for (idx=1; idx<NPROTO; idx++) {
 659                 int type = cb->nlh->nlmsg_type-RTM_BASE;
 660                 if (idx < s_idx || idx == PF_PACKET)
 661                         continue;
 662                 if (rtnetlink_links[idx] == NULL ||
 663                     rtnetlink_links[idx][type].dumpit == NULL)
 664                         continue;
 665                 if (idx > s_idx)
 666                         memset(&cb->args[0], 0, sizeof(cb->args));
 667                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
 668                         break;
 669         }
 670         cb->family = idx;
 671
 672         return skb->len;
 673 }
 674
 675 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
 676 {
 677         struct sk_buff *skb;
 678         int err = -ENOBUFS;
 679
 680         skb = nlmsg_new(if_nlmsg_size(0), GFP_KERNEL);
 681         if (skb == NULL)
 682                 goto errout;
 683
 684         err = rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0);
 685         /* failure implies BUG in if_nlmsg_size() */
 686         BUG_ON(err < 0);
 687
 688         err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
 689 errout:
 690         if (err < 0)
 691                 rtnl_set_sk_err(RTNLGRP_LINK, err);
 692 }
 693
 694 /* Protected by RTNL sempahore.  */
 695 static struct rtattr **rta_buf;
 696 static int rtattr_max;
 697
 698 /* Process one rtnetlink message. */
 699
 700 static __inline__ int
 701 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 702 {
 703         struct rtnetlink_link *link;
 704         struct rtnetlink_link *link_tab;
 705         int sz_idx, kind;
 706         int min_len;
 707         int family;
 708         int type;
 709         int err;
 710
 711         /* Only requests are handled by kernel now */
 712         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 713                 return 0;
 714
 715         type = nlh->nlmsg_type;
 716
 717         /* A control message: ignore them */
 718         if (type < RTM_BASE)
 719                 return 0;
 720
 721         /* Unknown message: reply with EINVAL */
 722         if (type > RTM_MAX)
 723                 goto err_inval;
 724
 725         type -= RTM_BASE;
 726
 727         /* All the messages must have at least 1 byte length */
 728         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
 729                 return 0;
 730
 731         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
 732         if (family >= NPROTO) {
 733                 *errp = -EAFNOSUPPORT;
 734                 return -1;
 735         }
 736
 737         link_tab = rtnetlink_links[family];
 738         if (link_tab == NULL)
 739                 link_tab = rtnetlink_links[PF_UNSPEC];
 740         link = &link_tab[type];
 741
 742         sz_idx = type>>2;
 743         kind = type&3;
 744
 745         if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN)) {
 746                 *errp = -EPERM;
 747                 return -1;
 748         }
 749
 750         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
 751                 if (link->dumpit == NULL)
 752                         link = &(rtnetlink_links[PF_UNSPEC][type]);
 753
 754                 if (link->dumpit == NULL)
 755                         goto err_inval;
 756
 757                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
 758                                                 link->dumpit, NULL)) != 0) {
 759                         return -1;
 760                 }
 761
 762                 netlink_queue_skip(nlh, skb);
 763                 return -1;
 764         }
 765
 766         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
 767
 768         min_len = rtm_min[sz_idx];
 769         if (nlh->nlmsg_len < min_len)
 770                 goto err_inval;
 771
 772         if (nlh->nlmsg_len > min_len) {
 773                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
 774                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
 775
 776                 while (RTA_OK(attr, attrlen)) {
 777                         unsigned flavor = attr->rta_type;
 778                         if (flavor) {
 779                                 if (flavor > rta_max[sz_idx])
 780                                         goto err_inval;
 781                                 rta_buf[flavor-1] = attr;
 782                         }
 783                         attr = RTA_NEXT(attr, attrlen);
 784                 }
 785         }
 786
 787         if (link->doit == NULL)
 788                 link = &(rtnetlink_links[PF_UNSPEC][type]);
 789         if (link->doit == NULL)
 790                 goto err_inval;
 791         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
 792
 793         *errp = err;
 794         return err;
 795
 796 err_inval:
 797         *errp = -EINVAL;
 798         return -1;
 799 }
 800
 801 static void rtnetlink_rcv(struct sock *sk, int len)
 802 {
 803         unsigned int qlen = 0;
 804
 805         do {
 806                 mutex_lock(&rtnl_mutex);
 807                 netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
 808                 mutex_unlock(&rtnl_mutex);
 809
 810                 netdev_run_todo();
 811         } while (qlen);
 812 }
 813
 814 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
 815 {
 816         [RTM_GETLINK     - RTM_BASE] = { .doit   = rtnl_getlink,
 817                                          .dumpit = rtnl_dump_ifinfo      },
 818         [RTM_SETLINK     - RTM_BASE] = { .doit   = rtnl_setlink          },
 819         [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 820         [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 821         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
 822         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
 823         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
 824 #ifdef CONFIG_FIB_RULES
 825         [RTM_NEWRULE     - RTM_BASE] = { .doit   = fib_nl_newrule        },
 826         [RTM_DELRULE     - RTM_BASE] = { .doit   = fib_nl_delrule        },
 827 #endif
 828         [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 829         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
 830         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
 831 };
 832
 833 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
 834 {
 835         struct net_device *dev = ptr;
 836         switch (event) {
 837         case NETDEV_UNREGISTER:
 838                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
 839                 break;
 840         case NETDEV_REGISTER:
 841                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
 842                 break;
 843         case NETDEV_UP:
 844         case NETDEV_DOWN:
 845                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
 846                 break;
 847         case NETDEV_CHANGE:
 848         case NETDEV_GOING_DOWN:
 849                 break;
 850         default:
 851                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
 852                 break;
 853         }
 854         return NOTIFY_DONE;
 855 }
 856
 857 static struct notifier_block rtnetlink_dev_notifier = {
 858         .notifier_call  = rtnetlink_event,
 859 };
 860
 861 void __init rtnetlink_init(void)
 862 {
 863         int i;
 864
 865         rtattr_max = 0;
 866         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
 867                 if (rta_max[i] > rtattr_max)
 868                         rtattr_max = rta_max[i];
 869         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
 870         if (!rta_buf)
 871                 panic("rtnetlink_init: cannot allocate rta_buf\n");
 872
 873         rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
 874                                      THIS_MODULE);
 875         if (rtnl == NULL)
 876                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
 877         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
 878         register_netdevice_notifier(&rtnetlink_dev_notifier);
 879         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
 880         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
 881 }
 882
 883 EXPORT_SYMBOL(__rta_fill);
 884 EXPORT_SYMBOL(rtattr_strlcpy);
 885 EXPORT_SYMBOL(rtattr_parse);
 886 EXPORT_SYMBOL(rtnetlink_links);
 887 EXPORT_SYMBOL(rtnetlink_put_metrics);
 888 EXPORT_SYMBOL(rtnl_lock);
 889 EXPORT_SYMBOL(rtnl_trylock);
 890 EXPORT_SYMBOL(rtnl_unlock);
 891 EXPORT_SYMBOL(rtnl_unicast);
 892 EXPORT_SYMBOL(rtnl_notify);
 893 EXPORT_SYMBOL(rtnl_set_sk_err);