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
  40 #include <asm/uaccess.h>
  41 #include <asm/system.h>
  42 #include <asm/string.h>
  43
  44 #include <linux/inet.h>
  45 #include <linux/netdevice.h>
  46 #include <net/ip.h>
  47 #include <net/protocol.h>
  48 #include <net/arp.h>
  49 #include <net/route.h>
  50 #include <net/udp.h>
  51 #include <net/sock.h>
  52 #include <net/pkt_sched.h>
  53 #include <net/fib_rules.h>
  54 #include <net/netlink.h>
  55 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
  56 #include <linux/wireless.h>
  57 #include <net/iw_handler.h>
  58 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
  59
  60 static DEFINE_MUTEX(rtnl_mutex);
  61
  62 void rtnl_lock(void)
  63 {
  64         mutex_lock(&rtnl_mutex);
  65 }
  66
  67 void __rtnl_unlock(void)
  68 {
  69         mutex_unlock(&rtnl_mutex);
  70 }
  71
  72 void rtnl_unlock(void)
  73 {
  74         mutex_unlock(&rtnl_mutex);
  75         if (rtnl && rtnl->sk_receive_queue.qlen)
  76                 rtnl->sk_data_ready(rtnl, 0);
  77         netdev_run_todo();
  78 }
  79
  80 int rtnl_trylock(void)
  81 {
  82         return mutex_trylock(&rtnl_mutex);
  83 }
  84
  85 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
  86 {
  87         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
  88
  89         while (RTA_OK(rta, len)) {
  90                 unsigned flavor = rta->rta_type;
  91                 if (flavor && flavor <= maxattr)
  92                         tb[flavor-1] = rta;
  93                 rta = RTA_NEXT(rta, len);
  94         }
  95         return 0;
  96 }
  97
  98 struct sock *rtnl;
  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_NEWPREFIX)]    = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 113         [RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 114         [RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 115 };
 116
 117 static const int rta_max[RTM_NR_FAMILIES] =
 118 {
 119         [RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
 120         [RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
 121         [RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
 122         [RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,
 123         [RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
 124         [RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
 125         [RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
 126         [RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
 127 };
 128
 129 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
 130 {
 131         struct rtattr *rta;
 132         int size = RTA_LENGTH(attrlen);
 133
 134         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
 135         rta->rta_type = attrtype;
 136         rta->rta_len = size;
 137         memcpy(RTA_DATA(rta), data, attrlen);
 138         memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
 139 }
 140
 141 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
 142 {
 143         size_t ret = RTA_PAYLOAD(rta);
 144         char *src = RTA_DATA(rta);
 145
 146         if (ret > 0 && src[ret - 1] == '\0')
 147                 ret--;
 148         if (size > 0) {
 149                 size_t len = (ret >= size) ? size - 1 : ret;
 150                 memset(dest, 0, size);
 151                 memcpy(dest, src, len);
 152         }
 153         return ret;
 154 }
 155
 156 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
 157 {
 158         int err = 0;
 159
 160         NETLINK_CB(skb).dst_group = group;
 161         if (echo)
 162                 atomic_inc(&skb->users);
 163         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
 164         if (echo)
 165                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 166         return err;
 167 }
 168
 169 int rtnl_unicast(struct sk_buff *skb, u32 pid)
 170 {
 171         return nlmsg_unicast(rtnl, skb, pid);
 172 }
 173
 174 int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
 175                 struct nlmsghdr *nlh, gfp_t flags)
 176 {
 177         int report = 0;
 178
 179         if (nlh)
 180                 report = nlmsg_report(nlh);
 181
 182         return nlmsg_notify(rtnl, skb, pid, group, report, flags);
 183 }
 184
 185 void rtnl_set_sk_err(u32 group, int error)
 186 {
 187         netlink_set_err(rtnl, 0, group, error);
 188 }
 189
 190 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
 191 {
 192         struct rtattr *mx = (struct rtattr*)skb->tail;
 193         int i;
 194
 195         RTA_PUT(skb, RTA_METRICS, 0, NULL);
 196         for (i=0; i<RTAX_MAX; i++) {
 197                 if (metrics[i])
 198                         RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
 199         }
 200         mx->rta_len = skb->tail - (u8*)mx;
 201         if (mx->rta_len == RTA_LENGTH(0))
 202                 skb_trim(skb, (u8*)mx - skb->data);
 203         return 0;
 204
 205 rtattr_failure:
 206         skb_trim(skb, (u8*)mx - skb->data);
 207         return -1;
 208 }
 209
 210
 211 static void set_operstate(struct net_device *dev, unsigned char transition)
 212 {
 213         unsigned char operstate = dev->operstate;
 214
 215         switch(transition) {
 216         case IF_OPER_UP:
 217                 if ((operstate == IF_OPER_DORMANT ||
 218                      operstate == IF_OPER_UNKNOWN) &&
 219                     !netif_dormant(dev))
 220                         operstate = IF_OPER_UP;
 221                 break;
 222
 223         case IF_OPER_DORMANT:
 224                 if (operstate == IF_OPER_UP ||
 225                     operstate == IF_OPER_UNKNOWN)
 226                         operstate = IF_OPER_DORMANT;
 227                 break;
 228         };
 229
 230         if (dev->operstate != operstate) {
 231                 write_lock_bh(&dev_base_lock);
 232                 dev->operstate = operstate;
 233                 write_unlock_bh(&dev_base_lock);
 234                 netdev_state_change(dev);
 235         }
 236 }
 237
 238 static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
 239                                  struct net_device_stats *b)
 240 {
 241         a->rx_packets = b->rx_packets;
 242         a->tx_packets = b->tx_packets;
 243         a->rx_bytes = b->rx_bytes;
 244         a->tx_bytes = b->tx_bytes;
 245         a->rx_errors = b->rx_errors;
 246         a->tx_errors = b->tx_errors;
 247         a->rx_dropped = b->rx_dropped;
 248         a->tx_dropped = b->tx_dropped;
 249
 250         a->multicast = b->multicast;
 251         a->collisions = b->collisions;
 252
 253         a->rx_length_errors = b->rx_length_errors;
 254         a->rx_over_errors = b->rx_over_errors;
 255         a->rx_crc_errors = b->rx_crc_errors;
 256         a->rx_frame_errors = b->rx_frame_errors;
 257         a->rx_fifo_errors = b->rx_fifo_errors;
 258         a->rx_missed_errors = b->rx_missed_errors;
 259
 260         a->tx_aborted_errors = b->tx_aborted_errors;
 261         a->tx_carrier_errors = b->tx_carrier_errors;
 262         a->tx_fifo_errors = b->tx_fifo_errors;
 263         a->tx_heartbeat_errors = b->tx_heartbeat_errors;
 264         a->tx_window_errors = b->tx_window_errors;
 265
 266         a->rx_compressed = b->rx_compressed;
 267         a->tx_compressed = b->tx_compressed;
 268 };
 269
 270 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 271                             void *iwbuf, int iwbuflen, int type, u32 pid,
 272                             u32 seq, u32 change, unsigned int flags)
 273 {
 274         struct ifinfomsg *ifm;
 275         struct nlmsghdr *nlh;
 276
 277         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
 278         if (nlh == NULL)
 279                 return -ENOBUFS;
 280
 281         ifm = nlmsg_data(nlh);
 282         ifm->ifi_family = AF_UNSPEC;
 283         ifm->__ifi_pad = 0;
 284         ifm->ifi_type = dev->type;
 285         ifm->ifi_index = dev->ifindex;
 286         ifm->ifi_flags = dev_get_flags(dev);
 287         ifm->ifi_change = change;
 288
 289         NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
 290         NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
 291         NLA_PUT_U32(skb, IFLA_WEIGHT, dev->weight);
 292         NLA_PUT_U8(skb, IFLA_OPERSTATE,
 293                    netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
 294         NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
 295         NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
 296
 297         if (dev->ifindex != dev->iflink)
 298                 NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
 299
 300         if (dev->master)
 301                 NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
 302
 303         if (dev->qdisc_sleeping)
 304                 NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
 305
 306         if (1) {
 307                 struct rtnl_link_ifmap map = {
 308                         .mem_start   = dev->mem_start,
 309                         .mem_end     = dev->mem_end,
 310                         .base_addr   = dev->base_addr,
 311                         .irq         = dev->irq,
 312                         .dma         = dev->dma,
 313                         .port        = dev->if_port,
 314                 };
 315                 NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
 316         }
 317
 318         if (dev->addr_len) {
 319                 NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
 320                 NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
 321         }
 322
 323         if (dev->get_stats) {
 324                 struct net_device_stats *stats = dev->get_stats(dev);
 325                 if (stats) {
 326                         struct nlattr *attr;
 327
 328                         attr = nla_reserve(skb, IFLA_STATS,
 329                                            sizeof(struct rtnl_link_stats));
 330                         if (attr == NULL)
 331                                 goto nla_put_failure;
 332
 333                         copy_rtnl_link_stats(nla_data(attr), stats);
 334                 }
 335         }
 336
 337         if (iwbuf)
 338                 NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
 339
 340         return nlmsg_end(skb, nlh);
 341
 342 nla_put_failure:
 343         return nlmsg_cancel(skb, nlh);
 344 }
 345
 346 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 347 {
 348         int idx;
 349         int s_idx = cb->args[0];
 350         struct net_device *dev;
 351
 352         read_lock(&dev_base_lock);
 353         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
 354                 if (idx < s_idx)
 355                         continue;
 356                 if (rtnl_fill_ifinfo(skb, dev, NULL, 0, RTM_NEWLINK,
 357                                      NETLINK_CB(cb->skb).pid,
 358                                      cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
 359                         break;
 360         }
 361         read_unlock(&dev_base_lock);
 362         cb->args[0] = idx;
 363
 364         return skb->len;
 365 }
 366
 367 static struct nla_policy ifla_policy[IFLA_MAX+1] __read_mostly = {
 368         [IFLA_IFNAME]           = { .type = NLA_STRING },
 369         [IFLA_MAP]              = { .minlen = sizeof(struct rtnl_link_ifmap) },
 370         [IFLA_MTU]              = { .type = NLA_U32 },
 371         [IFLA_TXQLEN]           = { .type = NLA_U32 },
 372         [IFLA_WEIGHT]           = { .type = NLA_U32 },
 373         [IFLA_OPERSTATE]        = { .type = NLA_U8 },
 374         [IFLA_LINKMODE]         = { .type = NLA_U8 },
 375 };
 376
 377 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 378 {
 379         struct ifinfomsg *ifm;
 380         struct net_device *dev;
 381         int err, send_addr_notify = 0, modified = 0;
 382         struct nlattr *tb[IFLA_MAX+1];
 383         char ifname[IFNAMSIZ];
 384
 385         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 386         if (err < 0)
 387                 goto errout;
 388
 389         if (tb[IFLA_IFNAME] &&
 390             nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ) >= IFNAMSIZ)
 391                 return -EINVAL;
 392
 393         err = -EINVAL;
 394         ifm = nlmsg_data(nlh);
 395         if (ifm->ifi_index >= 0)
 396                 dev = dev_get_by_index(ifm->ifi_index);
 397         else if (tb[IFLA_IFNAME])
 398                 dev = dev_get_by_name(ifname);
 399         else
 400                 goto errout;
 401
 402         if (dev == NULL) {
 403                 err = -ENODEV;
 404                 goto errout;
 405         }
 406
 407         if (tb[IFLA_ADDRESS] &&
 408             nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
 409                 goto errout_dev;
 410
 411         if (tb[IFLA_BROADCAST] &&
 412             nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
 413                 goto errout_dev;
 414
 415         if (tb[IFLA_MAP]) {
 416                 struct rtnl_link_ifmap *u_map;
 417                 struct ifmap k_map;
 418
 419                 if (!dev->set_config) {
 420                         err = -EOPNOTSUPP;
 421                         goto errout_dev;
 422                 }
 423
 424                 if (!netif_device_present(dev)) {
 425                         err = -ENODEV;
 426                         goto errout_dev;
 427                 }
 428
 429                 u_map = nla_data(tb[IFLA_MAP]);
 430                 k_map.mem_start = (unsigned long) u_map->mem_start;
 431                 k_map.mem_end = (unsigned long) u_map->mem_end;
 432                 k_map.base_addr = (unsigned short) u_map->base_addr;
 433                 k_map.irq = (unsigned char) u_map->irq;
 434                 k_map.dma = (unsigned char) u_map->dma;
 435                 k_map.port = (unsigned char) u_map->port;
 436
 437                 err = dev->set_config(dev, &k_map);
 438                 if (err < 0)
 439                         goto errout_dev;
 440
 441                 modified = 1;
 442         }
 443
 444         if (tb[IFLA_ADDRESS]) {
 445                 struct sockaddr *sa;
 446                 int len;
 447
 448                 if (!dev->set_mac_address) {
 449                         err = -EOPNOTSUPP;
 450                         goto errout_dev;
 451                 }
 452
 453                 if (!netif_device_present(dev)) {
 454                         err = -ENODEV;
 455                         goto errout_dev;
 456                 }
 457
 458                 len = sizeof(sa_family_t) + dev->addr_len;
 459                 sa = kmalloc(len, GFP_KERNEL);
 460                 if (!sa) {
 461                         err = -ENOMEM;
 462                         goto errout_dev;
 463                 }
 464                 sa->sa_family = dev->type;
 465                 memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
 466                        dev->addr_len);
 467                 err = dev->set_mac_address(dev, sa);
 468                 kfree(sa);
 469                 if (err)
 470                         goto errout_dev;
 471                 send_addr_notify = 1;
 472                 modified = 1;
 473         }
 474
 475         if (tb[IFLA_MTU]) {
 476                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 477                 if (err < 0)
 478                         goto errout_dev;
 479                 modified = 1;
 480         }
 481
 482         /*
 483          * Interface selected by interface index but interface
 484          * name provided implies that a name change has been
 485          * requested.
 486          */
 487         if (ifm->ifi_index >= 0 && ifname[0]) {
 488                 err = dev_change_name(dev, ifname);
 489                 if (err < 0)
 490                         goto errout_dev;
 491                 modified = 1;
 492         }
 493
 494 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 495         if (tb[IFLA_WIRELESS]) {
 496                 /* Call Wireless Extensions.
 497                  * Various stuff checked in there... */
 498                 err = wireless_rtnetlink_set(dev, nla_data(tb[IFLA_WIRELESS]),
 499                                              nla_len(tb[IFLA_WIRELESS]));
 500                 if (err < 0)
 501                         goto errout_dev;
 502         }
 503 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 504
 505         if (tb[IFLA_BROADCAST]) {
 506                 nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
 507                 send_addr_notify = 1;
 508         }
 509
 510
 511         if (ifm->ifi_flags)
 512                 dev_change_flags(dev, ifm->ifi_flags);
 513
 514         if (tb[IFLA_TXQLEN])
 515                 dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
 516
 517         if (tb[IFLA_WEIGHT])
 518                 dev->weight = nla_get_u32(tb[IFLA_WEIGHT]);
 519
 520         if (tb[IFLA_OPERSTATE])
 521                 set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
 522
 523         if (tb[IFLA_LINKMODE]) {
 524                 write_lock_bh(&dev_base_lock);
 525                 dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
 526                 write_unlock_bh(&dev_base_lock);
 527         }
 528
 529         err = 0;
 530
 531 errout_dev:
 532         if (err < 0 && modified && net_ratelimit())
 533                 printk(KERN_WARNING "A link change request failed with "
 534                        "some changes comitted already. Interface %s may "
 535                        "have been left with an inconsistent configuration, "
 536                        "please check.\n", dev->name);
 537
 538         if (send_addr_notify)
 539                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 540
 541         dev_put(dev);
 542 errout:
 543         return err;
 544 }
 545
 546 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 547 {
 548         struct ifinfomsg *ifm;
 549         struct nlattr *tb[IFLA_MAX+1];
 550         struct net_device *dev = NULL;
 551         struct sk_buff *nskb;
 552         char *iw_buf = NULL, *iw = NULL;
 553         int iw_buf_len = 0;
 554         int err, payload;
 555
 556         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 557         if (err < 0)
 558                 goto errout;
 559
 560         ifm = nlmsg_data(nlh);
 561         if (ifm->ifi_index >= 0) {
 562                 dev = dev_get_by_index(ifm->ifi_index);
 563                 if (dev == NULL)
 564                         return -ENODEV;
 565         } else
 566                 return -EINVAL;
 567
 568
 569 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 570         if (tb[IFLA_WIRELESS]) {
 571                 /* Call Wireless Extensions. We need to know the size before
 572                  * we can alloc. Various stuff checked in there... */
 573                 err = wireless_rtnetlink_get(dev, nla_data(tb[IFLA_WIRELESS]),
 574                                              nla_len(tb[IFLA_WIRELESS]),
 575                                              &iw_buf, &iw_buf_len);
 576                 if (err < 0)
 577                         goto errout;
 578
 579                 iw += IW_EV_POINT_OFF;
 580         }
 581 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 582
 583         payload = NLMSG_ALIGN(sizeof(struct ifinfomsg) +
 584                               nla_total_size(iw_buf_len));
 585         nskb = nlmsg_new(nlmsg_total_size(payload), GFP_KERNEL);
 586         if (nskb == NULL) {
 587                 err = -ENOBUFS;
 588                 goto errout;
 589         }
 590
 591         err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK,
 592                                NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0);
 593         if (err <= 0) {
 594                 kfree_skb(skb);
 595                 goto errout;
 596         }
 597
 598         err = rtnl_unicast(skb, NETLINK_CB(skb).pid);
 599 errout:
 600         kfree(iw_buf);
 601         dev_put(dev);
 602
 603         return err;
 604 }
 605
 606 static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 607 {
 608         int idx;
 609         int s_idx = cb->family;
 610
 611         if (s_idx == 0)
 612                 s_idx = 1;
 613         for (idx=1; idx<NPROTO; idx++) {
 614                 int type = cb->nlh->nlmsg_type-RTM_BASE;
 615                 if (idx < s_idx || idx == PF_PACKET)
 616                         continue;
 617                 if (rtnetlink_links[idx] == NULL ||
 618                     rtnetlink_links[idx][type].dumpit == NULL)
 619                         continue;
 620                 if (idx > s_idx)
 621                         memset(&cb->args[0], 0, sizeof(cb->args));
 622                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
 623                         break;
 624         }
 625         cb->family = idx;
 626
 627         return skb->len;
 628 }
 629
 630 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
 631 {
 632         struct sk_buff *skb;
 633         int err = -ENOBUFS;
 634
 635         skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 636         if (skb == NULL)
 637                 goto errout;
 638
 639         err = rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0);
 640         if (err < 0) {
 641                 kfree_skb(skb);
 642                 goto errout;
 643         }
 644
 645         err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
 646 errout:
 647         if (err < 0)
 648                 rtnl_set_sk_err(RTNLGRP_LINK, err);
 649 }
 650
 651 /* Protected by RTNL sempahore.  */
 652 static struct rtattr **rta_buf;
 653 static int rtattr_max;
 654
 655 /* Process one rtnetlink message. */
 656
 657 static __inline__ int
 658 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 659 {
 660         struct rtnetlink_link *link;
 661         struct rtnetlink_link *link_tab;
 662         int sz_idx, kind;
 663         int min_len;
 664         int family;
 665         int type;
 666         int err;
 667
 668         /* Only requests are handled by kernel now */
 669         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 670                 return 0;
 671
 672         type = nlh->nlmsg_type;
 673
 674         /* A control message: ignore them */
 675         if (type < RTM_BASE)
 676                 return 0;
 677
 678         /* Unknown message: reply with EINVAL */
 679         if (type > RTM_MAX)
 680                 goto err_inval;
 681
 682         type -= RTM_BASE;
 683
 684         /* All the messages must have at least 1 byte length */
 685         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
 686                 return 0;
 687
 688         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
 689         if (family >= NPROTO) {
 690                 *errp = -EAFNOSUPPORT;
 691                 return -1;
 692         }
 693
 694         link_tab = rtnetlink_links[family];
 695         if (link_tab == NULL)
 696                 link_tab = rtnetlink_links[PF_UNSPEC];
 697         link = &link_tab[type];
 698
 699         sz_idx = type>>2;
 700         kind = type&3;
 701
 702         if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN)) {
 703                 *errp = -EPERM;
 704                 return -1;
 705         }
 706
 707         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
 708                 if (link->dumpit == NULL)
 709                         link = &(rtnetlink_links[PF_UNSPEC][type]);
 710
 711                 if (link->dumpit == NULL)
 712                         goto err_inval;
 713
 714                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
 715                                                 link->dumpit, NULL)) != 0) {
 716                         return -1;
 717                 }
 718
 719                 netlink_queue_skip(nlh, skb);
 720                 return -1;
 721         }
 722
 723         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
 724
 725         min_len = rtm_min[sz_idx];
 726         if (nlh->nlmsg_len < min_len)
 727                 goto err_inval;
 728
 729         if (nlh->nlmsg_len > min_len) {
 730                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
 731                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
 732
 733                 while (RTA_OK(attr, attrlen)) {
 734                         unsigned flavor = attr->rta_type;
 735                         if (flavor) {
 736                                 if (flavor > rta_max[sz_idx])
 737                                         goto err_inval;
 738                                 rta_buf[flavor-1] = attr;
 739                         }
 740                         attr = RTA_NEXT(attr, attrlen);
 741                 }
 742         }
 743
 744         if (link->doit == NULL)
 745                 link = &(rtnetlink_links[PF_UNSPEC][type]);
 746         if (link->doit == NULL)
 747                 goto err_inval;
 748         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
 749
 750         *errp = err;
 751         return err;
 752
 753 err_inval:
 754         *errp = -EINVAL;
 755         return -1;
 756 }
 757
 758 static void rtnetlink_rcv(struct sock *sk, int len)
 759 {
 760         unsigned int qlen = 0;
 761
 762         do {
 763                 mutex_lock(&rtnl_mutex);
 764                 netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
 765                 mutex_unlock(&rtnl_mutex);
 766
 767                 netdev_run_todo();
 768         } while (qlen);
 769 }
 770
 771 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
 772 {
 773         [RTM_GETLINK     - RTM_BASE] = { .doit   = rtnl_getlink,
 774                                          .dumpit = rtnl_dump_ifinfo      },
 775         [RTM_SETLINK     - RTM_BASE] = { .doit   = rtnl_setlink          },
 776         [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 777         [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 778         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
 779         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
 780         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
 781 #ifdef CONFIG_FIB_RULES
 782         [RTM_NEWRULE     - RTM_BASE] = { .doit   = fib_nl_newrule        },
 783         [RTM_DELRULE     - RTM_BASE] = { .doit   = fib_nl_delrule        },
 784 #endif
 785         [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
 786         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
 787         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
 788 };
 789
 790 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
 791 {
 792         struct net_device *dev = ptr;
 793         switch (event) {
 794         case NETDEV_UNREGISTER:
 795                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
 796                 break;
 797         case NETDEV_REGISTER:
 798                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
 799                 break;
 800         case NETDEV_UP:
 801         case NETDEV_DOWN:
 802                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
 803                 break;
 804         case NETDEV_CHANGE:
 805         case NETDEV_GOING_DOWN:
 806                 break;
 807         default:
 808                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
 809                 break;
 810         }
 811         return NOTIFY_DONE;
 812 }
 813
 814 static struct notifier_block rtnetlink_dev_notifier = {
 815         .notifier_call  = rtnetlink_event,
 816 };
 817
 818 void __init rtnetlink_init(void)
 819 {
 820         int i;
 821
 822         rtattr_max = 0;
 823         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
 824                 if (rta_max[i] > rtattr_max)
 825                         rtattr_max = rta_max[i];
 826         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
 827         if (!rta_buf)
 828                 panic("rtnetlink_init: cannot allocate rta_buf\n");
 829
 830         rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
 831                                      THIS_MODULE);
 832         if (rtnl == NULL)
 833                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
 834         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
 835         register_netdevice_notifier(&rtnetlink_dev_notifier);
 836         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
 837         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
 838 }
 839
 840 EXPORT_SYMBOL(__rta_fill);
 841 EXPORT_SYMBOL(rtattr_strlcpy);
 842 EXPORT_SYMBOL(rtattr_parse);
 843 EXPORT_SYMBOL(rtnetlink_links);
 844 EXPORT_SYMBOL(rtnetlink_put_metrics);
 845 EXPORT_SYMBOL(rtnl);
 846 EXPORT_SYMBOL(rtnl_lock);
 847 EXPORT_SYMBOL(rtnl_trylock);
 848 EXPORT_SYMBOL(rtnl_unlock);
 849 EXPORT_SYMBOL(rtnl_unicast);
 850 EXPORT_SYMBOL(rtnl_notify);
 851 EXPORT_SYMBOL(rtnl_set_sk_err);