net/ieee802154/nl802154.c

   1 /* This program is free software; you can redistribute it and/or modify
   2  * it under the terms of the GNU General Public License version 2
   3  * as published by the Free Software Foundation.
   4  *
   5  * This program is distributed in the hope that it will be useful,
   6  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   7  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   8  * GNU General Public License for more details.
   9  *
  10  * Authors:
  11  * Alexander Aring <aar@pengutronix.de>
  12  *
  13  * Based on: net/wireless/nl80211.c
  14  */
  15
  16 #include <linux/rtnetlink.h>
  17
  18 #include <net/cfg802154.h>
  19 #include <net/genetlink.h>
  20 #include <net/mac802154.h>
  21 #include <net/netlink.h>
  22 #include <net/nl802154.h>
  23 #include <net/sock.h>
  24
  25 #include "nl802154.h"
  26 #include "rdev-ops.h"
  27 #include "core.h"
  28
  29 static int nl802154_pre_doit(const struct genl_ops *ops, struct sk_buff *skb,
  30                              struct genl_info *info);
  31
  32 static void nl802154_post_doit(const struct genl_ops *ops, struct sk_buff *skb,
  33                                struct genl_info *info);
  34
  35 /* the netlink family */
  36 static struct genl_family nl802154_fam = {
  37         .id = GENL_ID_GENERATE,         /* don't bother with a hardcoded ID */
  38         .name = NL802154_GENL_NAME,     /* have users key off the name instead */
  39         .hdrsize = 0,                   /* no private header */
  40         .version = 1,                   /* no particular meaning now */
  41         .maxattr = NL802154_ATTR_MAX,
  42         .netnsok = true,
  43         .pre_doit = nl802154_pre_doit,
  44         .post_doit = nl802154_post_doit,
  45 };
  46
  47 /* multicast groups */
  48 enum nl802154_multicast_groups {
  49         NL802154_MCGRP_CONFIG,
  50 };
  51
  52 static const struct genl_multicast_group nl802154_mcgrps[] = {
  53         [NL802154_MCGRP_CONFIG] = { .name = "config", },
  54 };
  55
  56 /* returns ERR_PTR values */
  57 static struct wpan_dev *
  58 __cfg802154_wpan_dev_from_attrs(struct net *netns, struct nlattr **attrs)
  59 {
  60         struct cfg802154_registered_device *rdev;
  61         struct wpan_dev *result = NULL;
  62         bool have_ifidx = attrs[NL802154_ATTR_IFINDEX];
  63         bool have_wpan_dev_id = attrs[NL802154_ATTR_WPAN_DEV];
  64         u64 wpan_dev_id;
  65         int wpan_phy_idx = -1;
  66         int ifidx = -1;
  67
  68         ASSERT_RTNL();
  69
  70         if (!have_ifidx && !have_wpan_dev_id)
  71                 return ERR_PTR(-EINVAL);
  72
  73         if (have_ifidx)
  74                 ifidx = nla_get_u32(attrs[NL802154_ATTR_IFINDEX]);
  75         if (have_wpan_dev_id) {
  76                 wpan_dev_id = nla_get_u64(attrs[NL802154_ATTR_WPAN_DEV]);
  77                 wpan_phy_idx = wpan_dev_id >> 32;
  78         }
  79
  80         list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
  81                 struct wpan_dev *wpan_dev;
  82
  83                 /* TODO netns compare */
  84
  85                 if (have_wpan_dev_id && rdev->wpan_phy_idx != wpan_phy_idx)
  86                         continue;
  87
  88                 list_for_each_entry(wpan_dev, &rdev->wpan_dev_list, list) {
  89                         if (have_ifidx && wpan_dev->netdev &&
  90                             wpan_dev->netdev->ifindex == ifidx) {
  91                                 result = wpan_dev;
  92                                 break;
  93                         }
  94                         if (have_wpan_dev_id &&
  95                             wpan_dev->identifier == (u32)wpan_dev_id) {
  96                                 result = wpan_dev;
  97                                 break;
  98                         }
  99                 }
 100
 101                 if (result)
 102                         break;
 103         }
 104
 105         if (result)
 106                 return result;
 107
 108         return ERR_PTR(-ENODEV);
 109 }
 110
 111 static struct cfg802154_registered_device *
 112 __cfg802154_rdev_from_attrs(struct net *netns, struct nlattr **attrs)
 113 {
 114         struct cfg802154_registered_device *rdev = NULL, *tmp;
 115         struct net_device *netdev;
 116
 117         ASSERT_RTNL();
 118
 119         if (!attrs[NL802154_ATTR_WPAN_PHY] &&
 120             !attrs[NL802154_ATTR_IFINDEX] &&
 121             !attrs[NL802154_ATTR_WPAN_DEV])
 122                 return ERR_PTR(-EINVAL);
 123
 124         if (attrs[NL802154_ATTR_WPAN_PHY])
 125                 rdev = cfg802154_rdev_by_wpan_phy_idx(
 126                                 nla_get_u32(attrs[NL802154_ATTR_WPAN_PHY]));
 127
 128         if (attrs[NL802154_ATTR_WPAN_DEV]) {
 129                 u64 wpan_dev_id = nla_get_u64(attrs[NL802154_ATTR_WPAN_DEV]);
 130                 struct wpan_dev *wpan_dev;
 131                 bool found = false;
 132
 133                 tmp = cfg802154_rdev_by_wpan_phy_idx(wpan_dev_id >> 32);
 134                 if (tmp) {
 135                         /* make sure wpan_dev exists */
 136                         list_for_each_entry(wpan_dev, &tmp->wpan_dev_list, list) {
 137                                 if (wpan_dev->identifier != (u32)wpan_dev_id)
 138                                         continue;
 139                                 found = true;
 140                                 break;
 141                         }
 142
 143                         if (!found)
 144                                 tmp = NULL;
 145
 146                         if (rdev && tmp != rdev)
 147                                 return ERR_PTR(-EINVAL);
 148                         rdev = tmp;
 149                 }
 150         }
 151
 152         if (attrs[NL802154_ATTR_IFINDEX]) {
 153                 int ifindex = nla_get_u32(attrs[NL802154_ATTR_IFINDEX]);
 154
 155                 netdev = __dev_get_by_index(netns, ifindex);
 156                 if (netdev) {
 157                         if (netdev->ieee802154_ptr)
 158                                 tmp = wpan_phy_to_rdev(
 159                                                 netdev->ieee802154_ptr->wpan_phy);
 160                         else
 161                                 tmp = NULL;
 162
 163                         /* not wireless device -- return error */
 164                         if (!tmp)
 165                                 return ERR_PTR(-EINVAL);
 166
 167                         /* mismatch -- return error */
 168                         if (rdev && tmp != rdev)
 169                                 return ERR_PTR(-EINVAL);
 170
 171                         rdev = tmp;
 172                 }
 173         }
 174
 175         if (!rdev)
 176                 return ERR_PTR(-ENODEV);
 177
 178         /* TODO netns compare */
 179
 180         return rdev;
 181 }
 182
 183 /* This function returns a pointer to the driver
 184  * that the genl_info item that is passed refers to.
 185  *
 186  * The result of this can be a PTR_ERR and hence must
 187  * be checked with IS_ERR() for errors.
 188  */
 189 static struct cfg802154_registered_device *
 190 cfg802154_get_dev_from_info(struct net *netns, struct genl_info *info)
 191 {
 192         return __cfg802154_rdev_from_attrs(netns, info->attrs);
 193 }
 194
 195 /* policy for the attributes */
 196 static const struct nla_policy nl802154_policy[NL802154_ATTR_MAX+1] = {
 197         [NL802154_ATTR_WPAN_PHY] = { .type = NLA_U32 },
 198         [NL802154_ATTR_WPAN_PHY_NAME] = { .type = NLA_NUL_STRING,
 199                                           .len = 20-1 },
 200
 201         [NL802154_ATTR_IFINDEX] = { .type = NLA_U32 },
 202         [NL802154_ATTR_IFTYPE] = { .type = NLA_U32 },
 203         [NL802154_ATTR_IFNAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ-1 },
 204
 205         [NL802154_ATTR_WPAN_DEV] = { .type = NLA_U64 },
 206
 207         [NL802154_ATTR_PAGE] = { .type = NLA_U8, },
 208         [NL802154_ATTR_CHANNEL] = { .type = NLA_U8, },
 209
 210         [NL802154_ATTR_TX_POWER] = { .type = NLA_S8, },
 211
 212         [NL802154_ATTR_CCA_MODE] = { .type = NLA_U8, },
 213
 214         [NL802154_ATTR_SUPPORTED_CHANNEL] = { .type = NLA_U32, },
 215
 216         [NL802154_ATTR_PAN_ID] = { .type = NLA_U16, },
 217         [NL802154_ATTR_EXTENDED_ADDR] = { .type = NLA_U64 },
 218         [NL802154_ATTR_SHORT_ADDR] = { .type = NLA_U16, },
 219
 220         [NL802154_ATTR_MIN_BE] = { .type = NLA_U8, },
 221         [NL802154_ATTR_MAX_BE] = { .type = NLA_U8, },
 222         [NL802154_ATTR_MAX_CSMA_BACKOFFS] = { .type = NLA_U8, },
 223
 224         [NL802154_ATTR_MAX_FRAME_RETRIES] = { .type = NLA_S8, },
 225
 226         [NL802154_ATTR_LBT_MODE] = { .type = NLA_U8, },
 227 };
 228
 229 /* message building helper */
 230 static inline void *nl802154hdr_put(struct sk_buff *skb, u32 portid, u32 seq,
 231                                     int flags, u8 cmd)
 232 {
 233         /* since there is no private header just add the generic one */
 234         return genlmsg_put(skb, portid, seq, &nl802154_fam, flags, cmd);
 235 }
 236
 237 static int
 238 nl802154_send_wpan_phy_channels(struct cfg802154_registered_device *rdev,
 239                                 struct sk_buff *msg)
 240 {
 241         struct nlattr *nl_page;
 242         unsigned long page;
 243
 244         nl_page = nla_nest_start(msg, NL802154_ATTR_CHANNELS_SUPPORTED);
 245         if (!nl_page)
 246                 return -ENOBUFS;
 247
 248         for (page = 0; page <= IEEE802154_MAX_PAGE; page++) {
 249                 if (nla_put_u32(msg, NL802154_ATTR_SUPPORTED_CHANNEL,
 250                                 rdev->wpan_phy.channels_supported[page]))
 251                         return -ENOBUFS;
 252         }
 253         nla_nest_end(msg, nl_page);
 254
 255         return 0;
 256 }
 257
 258 static int nl802154_send_wpan_phy(struct cfg802154_registered_device *rdev,
 259                                   enum nl802154_commands cmd,
 260                                   struct sk_buff *msg, u32 portid, u32 seq,
 261                                   int flags)
 262 {
 263         void *hdr;
 264
 265         hdr = nl802154hdr_put(msg, portid, seq, flags, cmd);
 266         if (!hdr)
 267                 return -ENOBUFS;
 268
 269         if (nla_put_u32(msg, NL802154_ATTR_WPAN_PHY, rdev->wpan_phy_idx) ||
 270             nla_put_string(msg, NL802154_ATTR_WPAN_PHY_NAME,
 271                            wpan_phy_name(&rdev->wpan_phy)) ||
 272             nla_put_u32(msg, NL802154_ATTR_GENERATION,
 273                         cfg802154_rdev_list_generation))
 274                 goto nla_put_failure;
 275
 276         if (cmd != NL802154_CMD_NEW_WPAN_PHY)
 277                 goto finish;
 278
 279         /* DUMP PHY PIB */
 280
 281         /* current channel settings */
 282         if (nla_put_u8(msg, NL802154_ATTR_PAGE,
 283                        rdev->wpan_phy.current_page) ||
 284             nla_put_u8(msg, NL802154_ATTR_CHANNEL,
 285                        rdev->wpan_phy.current_channel))
 286                 goto nla_put_failure;
 287
 288         /* supported channels array */
 289         if (nl802154_send_wpan_phy_channels(rdev, msg))
 290                 goto nla_put_failure;
 291
 292         /* cca mode */
 293         if (nla_put_u8(msg, NL802154_ATTR_CCA_MODE,
 294                        rdev->wpan_phy.cca_mode))
 295                 goto nla_put_failure;
 296
 297         if (nla_put_s8(msg, NL802154_ATTR_TX_POWER,
 298                        rdev->wpan_phy.transmit_power))
 299                 goto nla_put_failure;
 300
 301 finish:
 302         return genlmsg_end(msg, hdr);
 303
 304 nla_put_failure:
 305         genlmsg_cancel(msg, hdr);
 306         return -EMSGSIZE;
 307 }
 308
 309 struct nl802154_dump_wpan_phy_state {
 310         s64 filter_wpan_phy;
 311         long start;
 312
 313 };
 314
 315 static int nl802154_dump_wpan_phy_parse(struct sk_buff *skb,
 316                                         struct netlink_callback *cb,
 317                                         struct nl802154_dump_wpan_phy_state *state)
 318 {
 319         struct nlattr **tb = nl802154_fam.attrbuf;
 320         int ret = nlmsg_parse(cb->nlh, GENL_HDRLEN + nl802154_fam.hdrsize,
 321                               tb, nl802154_fam.maxattr, nl802154_policy);
 322
 323         /* TODO check if we can handle error here,
 324          * we have no backward compatibility
 325          */
 326         if (ret)
 327                 return 0;
 328
 329         if (tb[NL802154_ATTR_WPAN_PHY])
 330                 state->filter_wpan_phy = nla_get_u32(tb[NL802154_ATTR_WPAN_PHY]);
 331         if (tb[NL802154_ATTR_WPAN_DEV])
 332                 state->filter_wpan_phy = nla_get_u64(tb[NL802154_ATTR_WPAN_DEV]) >> 32;
 333         if (tb[NL802154_ATTR_IFINDEX]) {
 334                 struct net_device *netdev;
 335                 struct cfg802154_registered_device *rdev;
 336                 int ifidx = nla_get_u32(tb[NL802154_ATTR_IFINDEX]);
 337
 338                 /* TODO netns */
 339                 netdev = __dev_get_by_index(&init_net, ifidx);
 340                 if (!netdev)
 341                         return -ENODEV;
 342                 if (netdev->ieee802154_ptr) {
 343                         rdev = wpan_phy_to_rdev(
 344                                         netdev->ieee802154_ptr->wpan_phy);
 345                         state->filter_wpan_phy = rdev->wpan_phy_idx;
 346                 }
 347         }
 348
 349         return 0;
 350 }
 351
 352 static int
 353 nl802154_dump_wpan_phy(struct sk_buff *skb, struct netlink_callback *cb)
 354 {
 355         int idx = 0, ret;
 356         struct nl802154_dump_wpan_phy_state *state = (void *)cb->args[0];
 357         struct cfg802154_registered_device *rdev;
 358
 359         rtnl_lock();
 360         if (!state) {
 361                 state = kzalloc(sizeof(*state), GFP_KERNEL);
 362                 if (!state) {
 363                         rtnl_unlock();
 364                         return -ENOMEM;
 365                 }
 366                 state->filter_wpan_phy = -1;
 367                 ret = nl802154_dump_wpan_phy_parse(skb, cb, state);
 368                 if (ret) {
 369                         kfree(state);
 370                         rtnl_unlock();
 371                         return ret;
 372                 }
 373                 cb->args[0] = (long)state;
 374         }
 375
 376         list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
 377                 /* TODO net ns compare */
 378                 if (++idx <= state->start)
 379                         continue;
 380                 if (state->filter_wpan_phy != -1 &&
 381                     state->filter_wpan_phy != rdev->wpan_phy_idx)
 382                         continue;
 383                 /* attempt to fit multiple wpan_phy data chunks into the skb */
 384                 ret = nl802154_send_wpan_phy(rdev,
 385                                              NL802154_CMD_NEW_WPAN_PHY,
 386                                              skb,
 387                                              NETLINK_CB(cb->skb).portid,
 388                                              cb->nlh->nlmsg_seq, NLM_F_MULTI);
 389                 if (ret < 0) {
 390                         if ((ret == -ENOBUFS || ret == -EMSGSIZE) &&
 391                             !skb->len && cb->min_dump_alloc < 4096) {
 392                                 cb->min_dump_alloc = 4096;
 393                                 rtnl_unlock();
 394                                 return 1;
 395                         }
 396                         idx--;
 397                         break;
 398                 }
 399                 break;
 400         }
 401         rtnl_unlock();
 402
 403         state->start = idx;
 404
 405         return skb->len;
 406 }
 407
 408 static int nl802154_dump_wpan_phy_done(struct netlink_callback *cb)
 409 {
 410         kfree((void *)cb->args[0]);
 411         return 0;
 412 }
 413
 414 static int nl802154_get_wpan_phy(struct sk_buff *skb, struct genl_info *info)
 415 {
 416         struct sk_buff *msg;
 417         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 418
 419         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 420         if (!msg)
 421                 return -ENOMEM;
 422
 423         if (nl802154_send_wpan_phy(rdev, NL802154_CMD_NEW_WPAN_PHY, msg,
 424                                    info->snd_portid, info->snd_seq, 0) < 0) {
 425                 nlmsg_free(msg);
 426                 return -ENOBUFS;
 427         }
 428
 429         return genlmsg_reply(msg, info);
 430 }
 431
 432 static inline u64 wpan_dev_id(struct wpan_dev *wpan_dev)
 433 {
 434         return (u64)wpan_dev->identifier |
 435                ((u64)wpan_phy_to_rdev(wpan_dev->wpan_phy)->wpan_phy_idx << 32);
 436 }
 437
 438 static int
 439 nl802154_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flags,
 440                     struct cfg802154_registered_device *rdev,
 441                     struct wpan_dev *wpan_dev)
 442 {
 443         struct net_device *dev = wpan_dev->netdev;
 444         void *hdr;
 445
 446         hdr = nl802154hdr_put(msg, portid, seq, flags,
 447                               NL802154_CMD_NEW_INTERFACE);
 448         if (!hdr)
 449                 return -1;
 450
 451         if (dev &&
 452             (nla_put_u32(msg, NL802154_ATTR_IFINDEX, dev->ifindex) ||
 453              nla_put_string(msg, NL802154_ATTR_IFNAME, dev->name)))
 454                 goto nla_put_failure;
 455
 456         if (nla_put_u32(msg, NL802154_ATTR_WPAN_PHY, rdev->wpan_phy_idx) ||
 457             nla_put_u32(msg, NL802154_ATTR_IFTYPE, wpan_dev->iftype) ||
 458             nla_put_u64(msg, NL802154_ATTR_WPAN_DEV, wpan_dev_id(wpan_dev)) ||
 459             nla_put_u32(msg, NL802154_ATTR_GENERATION,
 460                         rdev->devlist_generation ^
 461                         (cfg802154_rdev_list_generation << 2)))
 462                 goto nla_put_failure;
 463
 464         /* address settings */
 465         if (nla_put_le64(msg, NL802154_ATTR_EXTENDED_ADDR,
 466                          wpan_dev->extended_addr) ||
 467             nla_put_le16(msg, NL802154_ATTR_SHORT_ADDR,
 468                          wpan_dev->short_addr) ||
 469             nla_put_le16(msg, NL802154_ATTR_PAN_ID, wpan_dev->pan_id))
 470                 goto nla_put_failure;
 471
 472         /* ARET handling */
 473         if (nla_put_s8(msg, NL802154_ATTR_MAX_FRAME_RETRIES,
 474                        wpan_dev->frame_retries) ||
 475             nla_put_u8(msg, NL802154_ATTR_MAX_BE, wpan_dev->max_be) ||
 476             nla_put_u8(msg, NL802154_ATTR_MAX_CSMA_BACKOFFS,
 477                        wpan_dev->csma_retries) ||
 478             nla_put_u8(msg, NL802154_ATTR_MIN_BE, wpan_dev->min_be))
 479                 goto nla_put_failure;
 480
 481         /* listen before transmit */
 482         if (nla_put_u8(msg, NL802154_ATTR_LBT_MODE, wpan_dev->lbt))
 483                 goto nla_put_failure;
 484
 485         return genlmsg_end(msg, hdr);
 486
 487 nla_put_failure:
 488         genlmsg_cancel(msg, hdr);
 489         return -EMSGSIZE;
 490 }
 491
 492 static int
 493 nl802154_dump_interface(struct sk_buff *skb, struct netlink_callback *cb)
 494 {
 495         int wp_idx = 0;
 496         int if_idx = 0;
 497         int wp_start = cb->args[0];
 498         int if_start = cb->args[1];
 499         struct cfg802154_registered_device *rdev;
 500         struct wpan_dev *wpan_dev;
 501
 502         rtnl_lock();
 503         list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
 504                 /* TODO netns compare */
 505                 if (wp_idx < wp_start) {
 506                         wp_idx++;
 507                         continue;
 508                 }
 509                 if_idx = 0;
 510
 511                 list_for_each_entry(wpan_dev, &rdev->wpan_dev_list, list) {
 512                         if (if_idx < if_start) {
 513                                 if_idx++;
 514                                 continue;
 515                         }
 516                         if (nl802154_send_iface(skb, NETLINK_CB(cb->skb).portid,
 517                                                 cb->nlh->nlmsg_seq, NLM_F_MULTI,
 518                                                 rdev, wpan_dev) < 0) {
 519                                 goto out;
 520                         }
 521                         if_idx++;
 522                 }
 523
 524                 wp_idx++;
 525         }
 526 out:
 527         rtnl_unlock();
 528
 529         cb->args[0] = wp_idx;
 530         cb->args[1] = if_idx;
 531
 532         return skb->len;
 533 }
 534
 535 static int nl802154_get_interface(struct sk_buff *skb, struct genl_info *info)
 536 {
 537         struct sk_buff *msg;
 538         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 539         struct wpan_dev *wdev = info->user_ptr[1];
 540
 541         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 542         if (!msg)
 543                 return -ENOMEM;
 544
 545         if (nl802154_send_iface(msg, info->snd_portid, info->snd_seq, 0,
 546                                 rdev, wdev) < 0) {
 547                 nlmsg_free(msg);
 548                 return -ENOBUFS;
 549         }
 550
 551         return genlmsg_reply(msg, info);
 552 }
 553
 554 static int nl802154_new_interface(struct sk_buff *skb, struct genl_info *info)
 555 {
 556         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 557         enum nl802154_iftype type = NL802154_IFTYPE_UNSPEC;
 558         __le64 extended_addr = cpu_to_le64(0x0000000000000000ULL);
 559
 560         /* TODO avoid failing a new interface
 561          * creation due to pending removal?
 562          */
 563
 564         if (!info->attrs[NL802154_ATTR_IFNAME])
 565                 return -EINVAL;
 566
 567         if (info->attrs[NL802154_ATTR_IFTYPE]) {
 568                 type = nla_get_u32(info->attrs[NL802154_ATTR_IFTYPE]);
 569                 if (type > NL802154_IFTYPE_MAX)
 570                         return -EINVAL;
 571         }
 572
 573         /* TODO add nla_get_le64 to netlink */
 574         if (info->attrs[NL802154_ATTR_EXTENDED_ADDR])
 575                 extended_addr = (__force __le64)nla_get_u64(
 576                                 info->attrs[NL802154_ATTR_EXTENDED_ADDR]);
 577
 578         if (!rdev->ops->add_virtual_intf)
 579                 return -EOPNOTSUPP;
 580
 581         return rdev_add_virtual_intf(rdev,
 582                                      nla_data(info->attrs[NL802154_ATTR_IFNAME]),
 583                                      type, extended_addr);
 584 }
 585
 586 static int nl802154_del_interface(struct sk_buff *skb, struct genl_info *info)
 587 {
 588         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 589         struct wpan_dev *wpan_dev = info->user_ptr[1];
 590
 591         if (!rdev->ops->del_virtual_intf)
 592                 return -EOPNOTSUPP;
 593
 594         /* If we remove a wpan device without a netdev then clear
 595          * user_ptr[1] so that nl802154_post_doit won't dereference it
 596          * to check if it needs to do dev_put(). Otherwise it crashes
 597          * since the wpan_dev has been freed, unlike with a netdev where
 598          * we need the dev_put() for the netdev to really be freed.
 599          */
 600         if (!wpan_dev->netdev)
 601                 info->user_ptr[1] = NULL;
 602
 603         return rdev_del_virtual_intf(rdev, wpan_dev);
 604 }
 605
 606 static int nl802154_set_channel(struct sk_buff *skb, struct genl_info *info)
 607 {
 608         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 609         u8 channel, page;
 610
 611         if (!info->attrs[NL802154_ATTR_PAGE] ||
 612             !info->attrs[NL802154_ATTR_CHANNEL])
 613                 return -EINVAL;
 614
 615         page = nla_get_u8(info->attrs[NL802154_ATTR_PAGE]);
 616         channel = nla_get_u8(info->attrs[NL802154_ATTR_CHANNEL]);
 617
 618         /* check 802.15.4 constraints */
 619         if (page > IEEE802154_MAX_PAGE || channel > IEEE802154_MAX_CHANNEL)
 620                 return -EINVAL;
 621
 622         return rdev_set_channel(rdev, page, channel);
 623 }
 624
 625 static int nl802154_set_pan_id(struct sk_buff *skb, struct genl_info *info)
 626 {
 627         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 628         struct net_device *dev = info->user_ptr[1];
 629         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 630         __le16 pan_id;
 631
 632         /* conflict here while tx/rx calls */
 633         if (netif_running(dev))
 634                 return -EBUSY;
 635
 636         /* don't change address fields on monitor */
 637         if (wpan_dev->iftype == NL802154_IFTYPE_MONITOR)
 638                 return -EINVAL;
 639
 640         if (!info->attrs[NL802154_ATTR_PAN_ID])
 641                 return -EINVAL;
 642
 643         pan_id = nla_get_le16(info->attrs[NL802154_ATTR_PAN_ID]);
 644
 645         return rdev_set_pan_id(rdev, wpan_dev, pan_id);
 646 }
 647
 648 static int nl802154_set_short_addr(struct sk_buff *skb, struct genl_info *info)
 649 {
 650         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 651         struct net_device *dev = info->user_ptr[1];
 652         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 653         __le16 short_addr;
 654
 655         /* conflict here while tx/rx calls */
 656         if (netif_running(dev))
 657                 return -EBUSY;
 658
 659         /* don't change address fields on monitor */
 660         if (wpan_dev->iftype == NL802154_IFTYPE_MONITOR)
 661                 return -EINVAL;
 662
 663         if (!info->attrs[NL802154_ATTR_SHORT_ADDR])
 664                 return -EINVAL;
 665
 666         short_addr = nla_get_le16(info->attrs[NL802154_ATTR_SHORT_ADDR]);
 667
 668         return rdev_set_short_addr(rdev, wpan_dev, short_addr);
 669 }
 670
 671 static int
 672 nl802154_set_backoff_exponent(struct sk_buff *skb, struct genl_info *info)
 673 {
 674         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 675         struct net_device *dev = info->user_ptr[1];
 676         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 677         u8 min_be, max_be;
 678
 679         /* should be set on netif open inside phy settings */
 680         if (netif_running(dev))
 681                 return -EBUSY;
 682
 683         if (!info->attrs[NL802154_ATTR_MIN_BE] ||
 684             !info->attrs[NL802154_ATTR_MAX_BE])
 685                 return -EINVAL;
 686
 687         min_be = nla_get_u8(info->attrs[NL802154_ATTR_MIN_BE]);
 688         max_be = nla_get_u8(info->attrs[NL802154_ATTR_MAX_BE]);
 689
 690         /* check 802.15.4 constraints */
 691         if (max_be < 3 || max_be > 8 || min_be > max_be)
 692                 return -EINVAL;
 693
 694         return rdev_set_backoff_exponent(rdev, wpan_dev, min_be, max_be);
 695 }
 696
 697 static int
 698 nl802154_set_max_csma_backoffs(struct sk_buff *skb, struct genl_info *info)
 699 {
 700         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 701         struct net_device *dev = info->user_ptr[1];
 702         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 703         u8 max_csma_backoffs;
 704
 705         /* conflict here while other running iface settings */
 706         if (netif_running(dev))
 707                 return -EBUSY;
 708
 709         if (!info->attrs[NL802154_ATTR_MAX_CSMA_BACKOFFS])
 710                 return -EINVAL;
 711
 712         max_csma_backoffs = nla_get_u8(
 713                         info->attrs[NL802154_ATTR_MAX_CSMA_BACKOFFS]);
 714
 715         /* check 802.15.4 constraints */
 716         if (max_csma_backoffs > 5)
 717                 return -EINVAL;
 718
 719         return rdev_set_max_csma_backoffs(rdev, wpan_dev, max_csma_backoffs);
 720 }
 721
 722 static int
 723 nl802154_set_max_frame_retries(struct sk_buff *skb, struct genl_info *info)
 724 {
 725         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 726         struct net_device *dev = info->user_ptr[1];
 727         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 728         s8 max_frame_retries;
 729
 730         if (netif_running(dev))
 731                 return -EBUSY;
 732
 733         if (!info->attrs[NL802154_ATTR_MAX_FRAME_RETRIES])
 734                 return -EINVAL;
 735
 736         max_frame_retries = nla_get_s8(
 737                         info->attrs[NL802154_ATTR_MAX_FRAME_RETRIES]);
 738
 739         /* check 802.15.4 constraints */
 740         if (max_frame_retries < -1 || max_frame_retries > 7)
 741                 return -EINVAL;
 742
 743         return rdev_set_max_frame_retries(rdev, wpan_dev, max_frame_retries);
 744 }
 745
 746 static int nl802154_set_lbt_mode(struct sk_buff *skb, struct genl_info *info)
 747 {
 748         struct cfg802154_registered_device *rdev = info->user_ptr[0];
 749         struct net_device *dev = info->user_ptr[1];
 750         struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 751         bool mode;
 752
 753         if (netif_running(dev))
 754                 return -EBUSY;
 755
 756         if (!info->attrs[NL802154_ATTR_LBT_MODE])
 757                 return -EINVAL;
 758
 759         mode = !!nla_get_u8(info->attrs[NL802154_ATTR_LBT_MODE]);
 760         return rdev_set_lbt_mode(rdev, wpan_dev, mode);
 761 }
 762
 763 #define NL802154_FLAG_NEED_WPAN_PHY     0x01
 764 #define NL802154_FLAG_NEED_NETDEV       0x02
 765 #define NL802154_FLAG_NEED_RTNL         0x04
 766 #define NL802154_FLAG_CHECK_NETDEV_UP   0x08
 767 #define NL802154_FLAG_NEED_NETDEV_UP    (NL802154_FLAG_NEED_NETDEV |\
 768                                          NL802154_FLAG_CHECK_NETDEV_UP)
 769 #define NL802154_FLAG_NEED_WPAN_DEV     0x10
 770 #define NL802154_FLAG_NEED_WPAN_DEV_UP  (NL802154_FLAG_NEED_WPAN_DEV |\
 771                                          NL802154_FLAG_CHECK_NETDEV_UP)
 772
 773 static int nl802154_pre_doit(const struct genl_ops *ops, struct sk_buff *skb,
 774                              struct genl_info *info)
 775 {
 776         struct cfg802154_registered_device *rdev;
 777         struct wpan_dev *wpan_dev;
 778         struct net_device *dev;
 779         bool rtnl = ops->internal_flags & NL802154_FLAG_NEED_RTNL;
 780
 781         if (rtnl)
 782                 rtnl_lock();
 783
 784         if (ops->internal_flags & NL802154_FLAG_NEED_WPAN_PHY) {
 785                 rdev = cfg802154_get_dev_from_info(genl_info_net(info), info);
 786                 if (IS_ERR(rdev)) {
 787                         if (rtnl)
 788                                 rtnl_unlock();
 789                         return PTR_ERR(rdev);
 790                 }
 791                 info->user_ptr[0] = rdev;
 792         } else if (ops->internal_flags & NL802154_FLAG_NEED_NETDEV ||
 793                    ops->internal_flags & NL802154_FLAG_NEED_WPAN_DEV) {
 794                 ASSERT_RTNL();
 795                 wpan_dev = __cfg802154_wpan_dev_from_attrs(genl_info_net(info),
 796                                                            info->attrs);
 797                 if (IS_ERR(wpan_dev)) {
 798                         if (rtnl)
 799                                 rtnl_unlock();
 800                         return PTR_ERR(wpan_dev);
 801                 }
 802
 803                 dev = wpan_dev->netdev;
 804                 rdev = wpan_phy_to_rdev(wpan_dev->wpan_phy);
 805
 806                 if (ops->internal_flags & NL802154_FLAG_NEED_NETDEV) {
 807                         if (!dev) {
 808                                 if (rtnl)
 809                                         rtnl_unlock();
 810                                 return -EINVAL;
 811                         }
 812
 813                         info->user_ptr[1] = dev;
 814                 } else {
 815                         info->user_ptr[1] = wpan_dev;
 816                 }
 817
 818                 if (dev) {
 819                         if (ops->internal_flags & NL802154_FLAG_CHECK_NETDEV_UP &&
 820                             !netif_running(dev)) {
 821                                 if (rtnl)
 822                                         rtnl_unlock();
 823                                 return -ENETDOWN;
 824                         }
 825
 826                         dev_hold(dev);
 827                 }
 828
 829                 info->user_ptr[0] = rdev;
 830         }
 831
 832         return 0;
 833 }
 834
 835 static void nl802154_post_doit(const struct genl_ops *ops, struct sk_buff *skb,
 836                                struct genl_info *info)
 837 {
 838         if (info->user_ptr[1]) {
 839                 if (ops->internal_flags & NL802154_FLAG_NEED_WPAN_DEV) {
 840                         struct wpan_dev *wpan_dev = info->user_ptr[1];
 841
 842                         if (wpan_dev->netdev)
 843                                 dev_put(wpan_dev->netdev);
 844                 } else {
 845                         dev_put(info->user_ptr[1]);
 846                 }
 847         }
 848
 849         if (ops->internal_flags & NL802154_FLAG_NEED_RTNL)
 850                 rtnl_unlock();
 851 }
 852
 853 static const struct genl_ops nl802154_ops[] = {
 854         {
 855                 .cmd = NL802154_CMD_GET_WPAN_PHY,
 856                 .doit = nl802154_get_wpan_phy,
 857                 .dumpit = nl802154_dump_wpan_phy,
 858                 .done = nl802154_dump_wpan_phy_done,
 859                 .policy = nl802154_policy,
 860                 /* can be retrieved by unprivileged users */
 861                 .internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 862                                   NL802154_FLAG_NEED_RTNL,
 863         },
 864         {
 865                 .cmd = NL802154_CMD_GET_INTERFACE,
 866                 .doit = nl802154_get_interface,
 867                 .dumpit = nl802154_dump_interface,
 868                 .policy = nl802154_policy,
 869                 /* can be retrieved by unprivileged users */
 870                 .internal_flags = NL802154_FLAG_NEED_WPAN_DEV |
 871                                   NL802154_FLAG_NEED_RTNL,
 872         },
 873         {
 874                 .cmd = NL802154_CMD_NEW_INTERFACE,
 875                 .doit = nl802154_new_interface,
 876                 .policy = nl802154_policy,
 877                 .flags = GENL_ADMIN_PERM,
 878                 .internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 879                                   NL802154_FLAG_NEED_RTNL,
 880         },
 881         {
 882                 .cmd = NL802154_CMD_DEL_INTERFACE,
 883                 .doit = nl802154_del_interface,
 884                 .policy = nl802154_policy,
 885                 .flags = GENL_ADMIN_PERM,
 886                 .internal_flags = NL802154_FLAG_NEED_WPAN_DEV |
 887                                   NL802154_FLAG_NEED_RTNL,
 888         },
 889         {
 890                 .cmd = NL802154_CMD_SET_CHANNEL,
 891                 .doit = nl802154_set_channel,
 892                 .policy = nl802154_policy,
 893                 .flags = GENL_ADMIN_PERM,
 894                 .internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 895                                   NL802154_FLAG_NEED_RTNL,
 896         },
 897         {
 898                 .cmd = NL802154_CMD_SET_PAN_ID,
 899                 .doit = nl802154_set_pan_id,
 900                 .policy = nl802154_policy,
 901                 .flags = GENL_ADMIN_PERM,
 902                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 903                                   NL802154_FLAG_NEED_RTNL,
 904         },
 905         {
 906                 .cmd = NL802154_CMD_SET_SHORT_ADDR,
 907                 .doit = nl802154_set_short_addr,
 908                 .policy = nl802154_policy,
 909                 .flags = GENL_ADMIN_PERM,
 910                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 911                                   NL802154_FLAG_NEED_RTNL,
 912         },
 913         {
 914                 .cmd = NL802154_CMD_SET_BACKOFF_EXPONENT,
 915                 .doit = nl802154_set_backoff_exponent,
 916                 .policy = nl802154_policy,
 917                 .flags = GENL_ADMIN_PERM,
 918                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 919                                   NL802154_FLAG_NEED_RTNL,
 920         },
 921         {
 922                 .cmd = NL802154_CMD_SET_MAX_CSMA_BACKOFFS,
 923                 .doit = nl802154_set_max_csma_backoffs,
 924                 .policy = nl802154_policy,
 925                 .flags = GENL_ADMIN_PERM,
 926                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 927                                   NL802154_FLAG_NEED_RTNL,
 928         },
 929         {
 930                 .cmd = NL802154_CMD_SET_MAX_FRAME_RETRIES,
 931                 .doit = nl802154_set_max_frame_retries,
 932                 .policy = nl802154_policy,
 933                 .flags = GENL_ADMIN_PERM,
 934                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 935                                   NL802154_FLAG_NEED_RTNL,
 936         },
 937         {
 938                 .cmd = NL802154_CMD_SET_LBT_MODE,
 939                 .doit = nl802154_set_lbt_mode,
 940                 .policy = nl802154_policy,
 941                 .flags = GENL_ADMIN_PERM,
 942                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
 943                                   NL802154_FLAG_NEED_RTNL,
 944         },
 945 };
 946
 947 /* initialisation/exit functions */
 948 int nl802154_init(void)
 949 {
 950         return genl_register_family_with_ops_groups(&nl802154_fam, nl802154_ops,
 951                                                     nl802154_mcgrps);
 952 }
 953
 954 void nl802154_exit(void)
 955 {
 956         genl_unregister_family(&nl802154_fam);
 957 }