net/netlabel/netlabel_mgmt.c

   1 /*
   2  * NetLabel Management Support
   3  *
   4  * This file defines the management functions for the NetLabel system.  The
   5  * NetLabel system manages static and dynamic label mappings for network
   6  * protocols such as CIPSO and RIPSO.
   7  *
   8  * Author: Paul Moore <paul@paul-moore.com>
   9  *
  10  */
  11
  12 /*
  13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008
  14  *
  15  * This program is free software;  you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  23  * the GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program;  if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  28  *
  29  */
  30
  31 #include <linux/types.h>
  32 #include <linux/socket.h>
  33 #include <linux/string.h>
  34 #include <linux/skbuff.h>
  35 #include <linux/in.h>
  36 #include <linux/in6.h>
  37 #include <linux/slab.h>
  38 #include <net/sock.h>
  39 #include <net/netlink.h>
  40 #include <net/genetlink.h>
  41 #include <net/ip.h>
  42 #include <net/ipv6.h>
  43 #include <net/netlabel.h>
  44 #include <net/cipso_ipv4.h>
  45 #include <linux/atomic.h>
  46
  47 #include "netlabel_domainhash.h"
  48 #include "netlabel_user.h"
  49 #include "netlabel_mgmt.h"
  50
  51 /* NetLabel configured protocol counter */
  52 atomic_t netlabel_mgmt_protocount = ATOMIC_INIT(0);
  53
  54 /* Argument struct for netlbl_domhsh_walk() */
  55 struct netlbl_domhsh_walk_arg {
  56         struct netlink_callback *nl_cb;
  57         struct sk_buff *skb;
  58         u32 seq;
  59 };
  60
  61 /* NetLabel Generic NETLINK CIPSOv4 family */
  62 static struct genl_family netlbl_mgmt_gnl_family = {
  63         .id = GENL_ID_GENERATE,
  64         .hdrsize = 0,
  65         .name = NETLBL_NLTYPE_MGMT_NAME,
  66         .version = NETLBL_PROTO_VERSION,
  67         .maxattr = NLBL_MGMT_A_MAX,
  68 };
  69
  70 /* NetLabel Netlink attribute policy */
  71 static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
  72         [NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
  73         [NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
  74         [NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
  75         [NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
  76 };
  77
  78 /*
  79  * Helper Functions
  80  */
  81
  82 /**
  83  * netlbl_mgmt_add - Handle an ADD message
  84  * @info: the Generic NETLINK info block
  85  * @audit_info: NetLabel audit information
  86  *
  87  * Description:
  88  * Helper function for the ADD and ADDDEF messages to add the domain mappings
  89  * from the message to the hash table.  See netlabel.h for a description of the
  90  * message format.  Returns zero on success, negative values on failure.
  91  *
  92  */
  93 static int netlbl_mgmt_add_common(struct genl_info *info,
  94                                   struct netlbl_audit *audit_info)
  95 {
  96         int ret_val = -EINVAL;
  97         struct netlbl_dom_map *entry = NULL;
  98         struct netlbl_domaddr_map *addrmap = NULL;
  99         struct cipso_v4_doi *cipsov4 = NULL;
 100         u32 tmp_val;
 101
 102         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 103         if (entry == NULL) {
 104                 ret_val = -ENOMEM;
 105                 goto add_failure;
 106         }
 107         entry->def.type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
 108         if (info->attrs[NLBL_MGMT_A_DOMAIN]) {
 109                 size_t tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
 110                 entry->domain = kmalloc(tmp_size, GFP_KERNEL);
 111                 if (entry->domain == NULL) {
 112                         ret_val = -ENOMEM;
 113                         goto add_failure;
 114                 }
 115                 nla_strlcpy(entry->domain,
 116                             info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
 117         }
 118
 119         /* NOTE: internally we allow/use a entry->def.type value of
 120          *       NETLBL_NLTYPE_ADDRSELECT but we don't currently allow users
 121          *       to pass that as a protocol value because we need to know the
 122          *       "real" protocol */
 123
 124         switch (entry->def.type) {
 125         case NETLBL_NLTYPE_UNLABELED:
 126                 break;
 127         case NETLBL_NLTYPE_CIPSOV4:
 128                 if (!info->attrs[NLBL_MGMT_A_CV4DOI])
 129                         goto add_failure;
 130
 131                 tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
 132                 cipsov4 = cipso_v4_doi_getdef(tmp_val);
 133                 if (cipsov4 == NULL)
 134                         goto add_failure;
 135                 entry->def.cipso = cipsov4;
 136                 break;
 137         default:
 138                 goto add_failure;
 139         }
 140
 141         if (info->attrs[NLBL_MGMT_A_IPV4ADDR]) {
 142                 struct in_addr *addr;
 143                 struct in_addr *mask;
 144                 struct netlbl_domaddr4_map *map;
 145
 146                 addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
 147                 if (addrmap == NULL) {
 148                         ret_val = -ENOMEM;
 149                         goto add_failure;
 150                 }
 151                 INIT_LIST_HEAD(&addrmap->list4);
 152                 INIT_LIST_HEAD(&addrmap->list6);
 153
 154                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV4ADDR]) !=
 155                     sizeof(struct in_addr)) {
 156                         ret_val = -EINVAL;
 157                         goto add_failure;
 158                 }
 159                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV4MASK]) !=
 160                     sizeof(struct in_addr)) {
 161                         ret_val = -EINVAL;
 162                         goto add_failure;
 163                 }
 164                 addr = nla_data(info->attrs[NLBL_MGMT_A_IPV4ADDR]);
 165                 mask = nla_data(info->attrs[NLBL_MGMT_A_IPV4MASK]);
 166
 167                 map = kzalloc(sizeof(*map), GFP_KERNEL);
 168                 if (map == NULL) {
 169                         ret_val = -ENOMEM;
 170                         goto add_failure;
 171                 }
 172                 map->list.addr = addr->s_addr & mask->s_addr;
 173                 map->list.mask = mask->s_addr;
 174                 map->list.valid = 1;
 175                 map->def.type = entry->def.type;
 176                 if (cipsov4)
 177                         map->def.cipso = cipsov4;
 178
 179                 ret_val = netlbl_af4list_add(&map->list, &addrmap->list4);
 180                 if (ret_val != 0) {
 181                         kfree(map);
 182                         goto add_failure;
 183                 }
 184
 185                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 186                 entry->def.addrsel = addrmap;
 187 #if IS_ENABLED(CONFIG_IPV6)
 188         } else if (info->attrs[NLBL_MGMT_A_IPV6ADDR]) {
 189                 struct in6_addr *addr;
 190                 struct in6_addr *mask;
 191                 struct netlbl_domaddr6_map *map;
 192
 193                 addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
 194                 if (addrmap == NULL) {
 195                         ret_val = -ENOMEM;
 196                         goto add_failure;
 197                 }
 198                 INIT_LIST_HEAD(&addrmap->list4);
 199                 INIT_LIST_HEAD(&addrmap->list6);
 200
 201                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV6ADDR]) !=
 202                     sizeof(struct in6_addr)) {
 203                         ret_val = -EINVAL;
 204                         goto add_failure;
 205                 }
 206                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV6MASK]) !=
 207                     sizeof(struct in6_addr)) {
 208                         ret_val = -EINVAL;
 209                         goto add_failure;
 210                 }
 211                 addr = nla_data(info->attrs[NLBL_MGMT_A_IPV6ADDR]);
 212                 mask = nla_data(info->attrs[NLBL_MGMT_A_IPV6MASK]);
 213
 214                 map = kzalloc(sizeof(*map), GFP_KERNEL);
 215                 if (map == NULL) {
 216                         ret_val = -ENOMEM;
 217                         goto add_failure;
 218                 }
 219                 map->list.addr = *addr;
 220                 map->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
 221                 map->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
 222                 map->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
 223                 map->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 224                 map->list.mask = *mask;
 225                 map->list.valid = 1;
 226                 map->def.type = entry->def.type;
 227
 228                 ret_val = netlbl_af6list_add(&map->list, &addrmap->list6);
 229                 if (ret_val != 0) {
 230                         kfree(map);
 231                         goto add_failure;
 232                 }
 233
 234                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 235                 entry->def.addrsel = addrmap;
 236 #endif /* IPv6 */
 237         }
 238
 239         ret_val = netlbl_domhsh_add(entry, audit_info);
 240         if (ret_val != 0)
 241                 goto add_failure;
 242
 243         return 0;
 244
 245 add_failure:
 246         if (cipsov4)
 247                 cipso_v4_doi_putdef(cipsov4);
 248         if (entry)
 249                 kfree(entry->domain);
 250         kfree(addrmap);
 251         kfree(entry);
 252         return ret_val;
 253 }
 254
 255 /**
 256  * netlbl_mgmt_listentry - List a NetLabel/LSM domain map entry
 257  * @skb: the NETLINK buffer
 258  * @entry: the map entry
 259  *
 260  * Description:
 261  * This function is a helper function used by the LISTALL and LISTDEF command
 262  * handlers.  The caller is responsible for ensuring that the RCU read lock
 263  * is held.  Returns zero on success, negative values on failure.
 264  *
 265  */
 266 static int netlbl_mgmt_listentry(struct sk_buff *skb,
 267                                  struct netlbl_dom_map *entry)
 268 {
 269         int ret_val = 0;
 270         struct nlattr *nla_a;
 271         struct nlattr *nla_b;
 272         struct netlbl_af4list *iter4;
 273 #if IS_ENABLED(CONFIG_IPV6)
 274         struct netlbl_af6list *iter6;
 275 #endif
 276
 277         if (entry->domain != NULL) {
 278                 ret_val = nla_put_string(skb,
 279                                          NLBL_MGMT_A_DOMAIN, entry->domain);
 280                 if (ret_val != 0)
 281                         return ret_val;
 282         }
 283
 284         switch (entry->def.type) {
 285         case NETLBL_NLTYPE_ADDRSELECT:
 286                 nla_a = nla_nest_start(skb, NLBL_MGMT_A_SELECTORLIST);
 287                 if (nla_a == NULL)
 288                         return -ENOMEM;
 289
 290                 netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) {
 291                         struct netlbl_domaddr4_map *map4;
 292                         struct in_addr addr_struct;
 293
 294                         nla_b = nla_nest_start(skb, NLBL_MGMT_A_ADDRSELECTOR);
 295                         if (nla_b == NULL)
 296                                 return -ENOMEM;
 297
 298                         addr_struct.s_addr = iter4->addr;
 299                         ret_val = nla_put(skb, NLBL_MGMT_A_IPV4ADDR,
 300                                           sizeof(struct in_addr),
 301                                           &addr_struct);
 302                         if (ret_val != 0)
 303                                 return ret_val;
 304                         addr_struct.s_addr = iter4->mask;
 305                         ret_val = nla_put(skb, NLBL_MGMT_A_IPV4MASK,
 306                                           sizeof(struct in_addr),
 307                                           &addr_struct);
 308                         if (ret_val != 0)
 309                                 return ret_val;
 310                         map4 = netlbl_domhsh_addr4_entry(iter4);
 311                         ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL,
 312                                               map4->def.type);
 313                         if (ret_val != 0)
 314                                 return ret_val;
 315                         switch (map4->def.type) {
 316                         case NETLBL_NLTYPE_CIPSOV4:
 317                                 ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI,
 318                                                       map4->def.cipso->doi);
 319                                 if (ret_val != 0)
 320                                         return ret_val;
 321                                 break;
 322                         }
 323
 324                         nla_nest_end(skb, nla_b);
 325                 }
 326 #if IS_ENABLED(CONFIG_IPV6)
 327                 netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) {
 328                         struct netlbl_domaddr6_map *map6;
 329
 330                         nla_b = nla_nest_start(skb, NLBL_MGMT_A_ADDRSELECTOR);
 331                         if (nla_b == NULL)
 332                                 return -ENOMEM;
 333
 334                         ret_val = nla_put(skb, NLBL_MGMT_A_IPV6ADDR,
 335                                           sizeof(struct in6_addr),
 336                                           &iter6->addr);
 337                         if (ret_val != 0)
 338                                 return ret_val;
 339                         ret_val = nla_put(skb, NLBL_MGMT_A_IPV6MASK,
 340                                           sizeof(struct in6_addr),
 341                                           &iter6->mask);
 342                         if (ret_val != 0)
 343                                 return ret_val;
 344                         map6 = netlbl_domhsh_addr6_entry(iter6);
 345                         ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL,
 346                                               map6->def.type);
 347                         if (ret_val != 0)
 348                                 return ret_val;
 349
 350                         nla_nest_end(skb, nla_b);
 351                 }
 352 #endif /* IPv6 */
 353
 354                 nla_nest_end(skb, nla_a);
 355                 break;
 356         case NETLBL_NLTYPE_UNLABELED:
 357                 ret_val = nla_put_u32(skb,NLBL_MGMT_A_PROTOCOL,entry->def.type);
 358                 break;
 359         case NETLBL_NLTYPE_CIPSOV4:
 360                 ret_val = nla_put_u32(skb,NLBL_MGMT_A_PROTOCOL,entry->def.type);
 361                 if (ret_val != 0)
 362                         return ret_val;
 363                 ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI,
 364                                       entry->def.cipso->doi);
 365                 break;
 366         }
 367
 368         return ret_val;
 369 }
 370
 371 /*
 372  * NetLabel Command Handlers
 373  */
 374
 375 /**
 376  * netlbl_mgmt_add - Handle an ADD message
 377  * @skb: the NETLINK buffer
 378  * @info: the Generic NETLINK info block
 379  *
 380  * Description:
 381  * Process a user generated ADD message and add the domains from the message
 382  * to the hash table.  See netlabel.h for a description of the message format.
 383  * Returns zero on success, negative values on failure.
 384  *
 385  */
 386 static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
 387 {
 388         struct netlbl_audit audit_info;
 389
 390         if ((!info->attrs[NLBL_MGMT_A_DOMAIN]) ||
 391             (!info->attrs[NLBL_MGMT_A_PROTOCOL]) ||
 392             (info->attrs[NLBL_MGMT_A_IPV4ADDR] &&
 393              info->attrs[NLBL_MGMT_A_IPV6ADDR]) ||
 394             (info->attrs[NLBL_MGMT_A_IPV4MASK] &&
 395              info->attrs[NLBL_MGMT_A_IPV6MASK]) ||
 396             ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^
 397              (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) ||
 398             ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^
 399              (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL)))
 400                 return -EINVAL;
 401
 402         netlbl_netlink_auditinfo(skb, &audit_info);
 403
 404         return netlbl_mgmt_add_common(info, &audit_info);
 405 }
 406
 407 /**
 408  * netlbl_mgmt_remove - Handle a REMOVE message
 409  * @skb: the NETLINK buffer
 410  * @info: the Generic NETLINK info block
 411  *
 412  * Description:
 413  * Process a user generated REMOVE message and remove the specified domain
 414  * mappings.  Returns zero on success, negative values on failure.
 415  *
 416  */
 417 static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
 418 {
 419         char *domain;
 420         struct netlbl_audit audit_info;
 421
 422         if (!info->attrs[NLBL_MGMT_A_DOMAIN])
 423                 return -EINVAL;
 424
 425         netlbl_netlink_auditinfo(skb, &audit_info);
 426
 427         domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
 428         return netlbl_domhsh_remove(domain, &audit_info);
 429 }
 430
 431 /**
 432  * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
 433  * @entry: the domain mapping hash table entry
 434  * @arg: the netlbl_domhsh_walk_arg structure
 435  *
 436  * Description:
 437  * This function is designed to be used as a callback to the
 438  * netlbl_domhsh_walk() function for use in generating a response for a LISTALL
 439  * message.  Returns the size of the message on success, negative values on
 440  * failure.
 441  *
 442  */
 443 static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
 444 {
 445         int ret_val = -ENOMEM;
 446         struct netlbl_domhsh_walk_arg *cb_arg = arg;
 447         void *data;
 448
 449         data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
 450                            cb_arg->seq, &netlbl_mgmt_gnl_family,
 451                            NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
 452         if (data == NULL)
 453                 goto listall_cb_failure;
 454
 455         ret_val = netlbl_mgmt_listentry(cb_arg->skb, entry);
 456         if (ret_val != 0)
 457                 goto listall_cb_failure;
 458
 459         cb_arg->seq++;
 460         return genlmsg_end(cb_arg->skb, data);
 461
 462 listall_cb_failure:
 463         genlmsg_cancel(cb_arg->skb, data);
 464         return ret_val;
 465 }
 466
 467 /**
 468  * netlbl_mgmt_listall - Handle a LISTALL message
 469  * @skb: the NETLINK buffer
 470  * @cb: the NETLINK callback
 471  *
 472  * Description:
 473  * Process a user generated LISTALL message and dumps the domain hash table in
 474  * a form suitable for use in a kernel generated LISTALL message.  Returns zero
 475  * on success, negative values on failure.
 476  *
 477  */
 478 static int netlbl_mgmt_listall(struct sk_buff *skb,
 479                                struct netlink_callback *cb)
 480 {
 481         struct netlbl_domhsh_walk_arg cb_arg;
 482         u32 skip_bkt = cb->args[0];
 483         u32 skip_chain = cb->args[1];
 484
 485         cb_arg.nl_cb = cb;
 486         cb_arg.skb = skb;
 487         cb_arg.seq = cb->nlh->nlmsg_seq;
 488
 489         netlbl_domhsh_walk(&skip_bkt,
 490                            &skip_chain,
 491                            netlbl_mgmt_listall_cb,
 492                            &cb_arg);
 493
 494         cb->args[0] = skip_bkt;
 495         cb->args[1] = skip_chain;
 496         return skb->len;
 497 }
 498
 499 /**
 500  * netlbl_mgmt_adddef - Handle an ADDDEF message
 501  * @skb: the NETLINK buffer
 502  * @info: the Generic NETLINK info block
 503  *
 504  * Description:
 505  * Process a user generated ADDDEF message and respond accordingly.  Returns
 506  * zero on success, negative values on failure.
 507  *
 508  */
 509 static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
 510 {
 511         struct netlbl_audit audit_info;
 512
 513         if ((!info->attrs[NLBL_MGMT_A_PROTOCOL]) ||
 514             (info->attrs[NLBL_MGMT_A_IPV4ADDR] &&
 515              info->attrs[NLBL_MGMT_A_IPV6ADDR]) ||
 516             (info->attrs[NLBL_MGMT_A_IPV4MASK] &&
 517              info->attrs[NLBL_MGMT_A_IPV6MASK]) ||
 518             ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^
 519              (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) ||
 520             ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^
 521              (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL)))
 522                 return -EINVAL;
 523
 524         netlbl_netlink_auditinfo(skb, &audit_info);
 525
 526         return netlbl_mgmt_add_common(info, &audit_info);
 527 }
 528
 529 /**
 530  * netlbl_mgmt_removedef - Handle a REMOVEDEF message
 531  * @skb: the NETLINK buffer
 532  * @info: the Generic NETLINK info block
 533  *
 534  * Description:
 535  * Process a user generated REMOVEDEF message and remove the default domain
 536  * mapping.  Returns zero on success, negative values on failure.
 537  *
 538  */
 539 static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
 540 {
 541         struct netlbl_audit audit_info;
 542
 543         netlbl_netlink_auditinfo(skb, &audit_info);
 544
 545         return netlbl_domhsh_remove_default(&audit_info);
 546 }
 547
 548 /**
 549  * netlbl_mgmt_listdef - Handle a LISTDEF message
 550  * @skb: the NETLINK buffer
 551  * @info: the Generic NETLINK info block
 552  *
 553  * Description:
 554  * Process a user generated LISTDEF message and dumps the default domain
 555  * mapping in a form suitable for use in a kernel generated LISTDEF message.
 556  * Returns zero on success, negative values on failure.
 557  *
 558  */
 559 static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
 560 {
 561         int ret_val = -ENOMEM;
 562         struct sk_buff *ans_skb = NULL;
 563         void *data;
 564         struct netlbl_dom_map *entry;
 565
 566         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 567         if (ans_skb == NULL)
 568                 return -ENOMEM;
 569         data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 570                                  0, NLBL_MGMT_C_LISTDEF);
 571         if (data == NULL)
 572                 goto listdef_failure;
 573
 574         rcu_read_lock();
 575         entry = netlbl_domhsh_getentry(NULL);
 576         if (entry == NULL) {
 577                 ret_val = -ENOENT;
 578                 goto listdef_failure_lock;
 579         }
 580         ret_val = netlbl_mgmt_listentry(ans_skb, entry);
 581         rcu_read_unlock();
 582         if (ret_val != 0)
 583                 goto listdef_failure;
 584
 585         genlmsg_end(ans_skb, data);
 586         return genlmsg_reply(ans_skb, info);
 587
 588 listdef_failure_lock:
 589         rcu_read_unlock();
 590 listdef_failure:
 591         kfree_skb(ans_skb);
 592         return ret_val;
 593 }
 594
 595 /**
 596  * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
 597  * @skb: the skb to write to
 598  * @cb: the NETLINK callback
 599  * @protocol: the NetLabel protocol to use in the message
 600  *
 601  * Description:
 602  * This function is to be used in conjunction with netlbl_mgmt_protocols() to
 603  * answer a application's PROTOCOLS message.  Returns the size of the message
 604  * on success, negative values on failure.
 605  *
 606  */
 607 static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
 608                                     struct netlink_callback *cb,
 609                                     u32 protocol)
 610 {
 611         int ret_val = -ENOMEM;
 612         void *data;
 613
 614         data = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 615                            &netlbl_mgmt_gnl_family, NLM_F_MULTI,
 616                            NLBL_MGMT_C_PROTOCOLS);
 617         if (data == NULL)
 618                 goto protocols_cb_failure;
 619
 620         ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
 621         if (ret_val != 0)
 622                 goto protocols_cb_failure;
 623
 624         return genlmsg_end(skb, data);
 625
 626 protocols_cb_failure:
 627         genlmsg_cancel(skb, data);
 628         return ret_val;
 629 }
 630
 631 /**
 632  * netlbl_mgmt_protocols - Handle a PROTOCOLS message
 633  * @skb: the NETLINK buffer
 634  * @cb: the NETLINK callback
 635  *
 636  * Description:
 637  * Process a user generated PROTOCOLS message and respond accordingly.
 638  *
 639  */
 640 static int netlbl_mgmt_protocols(struct sk_buff *skb,
 641                                  struct netlink_callback *cb)
 642 {
 643         u32 protos_sent = cb->args[0];
 644
 645         if (protos_sent == 0) {
 646                 if (netlbl_mgmt_protocols_cb(skb,
 647                                              cb,
 648                                              NETLBL_NLTYPE_UNLABELED) < 0)
 649                         goto protocols_return;
 650                 protos_sent++;
 651         }
 652         if (protos_sent == 1) {
 653                 if (netlbl_mgmt_protocols_cb(skb,
 654                                              cb,
 655                                              NETLBL_NLTYPE_CIPSOV4) < 0)
 656                         goto protocols_return;
 657                 protos_sent++;
 658         }
 659
 660 protocols_return:
 661         cb->args[0] = protos_sent;
 662         return skb->len;
 663 }
 664
 665 /**
 666  * netlbl_mgmt_version - Handle a VERSION message
 667  * @skb: the NETLINK buffer
 668  * @info: the Generic NETLINK info block
 669  *
 670  * Description:
 671  * Process a user generated VERSION message and respond accordingly.  Returns
 672  * zero on success, negative values on failure.
 673  *
 674  */
 675 static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info)
 676 {
 677         int ret_val = -ENOMEM;
 678         struct sk_buff *ans_skb = NULL;
 679         void *data;
 680
 681         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 682         if (ans_skb == NULL)
 683                 return -ENOMEM;
 684         data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 685                                  0, NLBL_MGMT_C_VERSION);
 686         if (data == NULL)
 687                 goto version_failure;
 688
 689         ret_val = nla_put_u32(ans_skb,
 690                               NLBL_MGMT_A_VERSION,
 691                               NETLBL_PROTO_VERSION);
 692         if (ret_val != 0)
 693                 goto version_failure;
 694
 695         genlmsg_end(ans_skb, data);
 696         return genlmsg_reply(ans_skb, info);
 697
 698 version_failure:
 699         kfree_skb(ans_skb);
 700         return ret_val;
 701 }
 702
 703
 704 /*
 705  * NetLabel Generic NETLINK Command Definitions
 706  */
 707
 708 static struct genl_ops netlbl_mgmt_genl_ops[] = {
 709         {
 710         .cmd = NLBL_MGMT_C_ADD,
 711         .flags = GENL_ADMIN_PERM,
 712         .policy = netlbl_mgmt_genl_policy,
 713         .doit = netlbl_mgmt_add,
 714         .dumpit = NULL,
 715         },
 716         {
 717         .cmd = NLBL_MGMT_C_REMOVE,
 718         .flags = GENL_ADMIN_PERM,
 719         .policy = netlbl_mgmt_genl_policy,
 720         .doit = netlbl_mgmt_remove,
 721         .dumpit = NULL,
 722         },
 723         {
 724         .cmd = NLBL_MGMT_C_LISTALL,
 725         .flags = 0,
 726         .policy = netlbl_mgmt_genl_policy,
 727         .doit = NULL,
 728         .dumpit = netlbl_mgmt_listall,
 729         },
 730         {
 731         .cmd = NLBL_MGMT_C_ADDDEF,
 732         .flags = GENL_ADMIN_PERM,
 733         .policy = netlbl_mgmt_genl_policy,
 734         .doit = netlbl_mgmt_adddef,
 735         .dumpit = NULL,
 736         },
 737         {
 738         .cmd = NLBL_MGMT_C_REMOVEDEF,
 739         .flags = GENL_ADMIN_PERM,
 740         .policy = netlbl_mgmt_genl_policy,
 741         .doit = netlbl_mgmt_removedef,
 742         .dumpit = NULL,
 743         },
 744         {
 745         .cmd = NLBL_MGMT_C_LISTDEF,
 746         .flags = 0,
 747         .policy = netlbl_mgmt_genl_policy,
 748         .doit = netlbl_mgmt_listdef,
 749         .dumpit = NULL,
 750         },
 751         {
 752         .cmd = NLBL_MGMT_C_PROTOCOLS,
 753         .flags = 0,
 754         .policy = netlbl_mgmt_genl_policy,
 755         .doit = NULL,
 756         .dumpit = netlbl_mgmt_protocols,
 757         },
 758         {
 759         .cmd = NLBL_MGMT_C_VERSION,
 760         .flags = 0,
 761         .policy = netlbl_mgmt_genl_policy,
 762         .doit = netlbl_mgmt_version,
 763         .dumpit = NULL,
 764         },
 765 };
 766
 767 /*
 768  * NetLabel Generic NETLINK Protocol Functions
 769  */
 770
 771 /**
 772  * netlbl_mgmt_genl_init - Register the NetLabel management component
 773  *
 774  * Description:
 775  * Register the NetLabel management component with the Generic NETLINK
 776  * mechanism.  Returns zero on success, negative values on failure.
 777  *
 778  */
 779 int __init netlbl_mgmt_genl_init(void)
 780 {
 781         return genl_register_family_with_ops(&netlbl_mgmt_gnl_family,
 782                 netlbl_mgmt_genl_ops, ARRAY_SIZE(netlbl_mgmt_genl_ops));
 783 }