git.oblomov.eu Git - linux-2.6/blob - net/netlabel/netlabel_cipso_v4.c

   1 /*
   2  * NetLabel CIPSO/IPv4 Support
   3  *
   4  * This file defines the CIPSO/IPv4 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.moore@hp.com>
   9  *
  10  */
  11
  12 /*
  13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
  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 <net/sock.h>
  36 #include <net/netlink.h>
  37 #include <net/genetlink.h>
  38 #include <net/netlabel.h>
  39 #include <net/cipso_ipv4.h>
  40
  41 #include "netlabel_user.h"
  42 #include "netlabel_cipso_v4.h"
  43
  44 /* Argument struct for cipso_v4_doi_walk() */
  45 struct netlbl_cipsov4_doiwalk_arg {
  46         struct netlink_callback *nl_cb;
  47         struct sk_buff *skb;
  48         u32 seq;
  49 };
  50
  51 /* NetLabel Generic NETLINK CIPSOv4 family */
  52 static struct genl_family netlbl_cipsov4_gnl_family = {
  53         .id = GENL_ID_GENERATE,
  54         .hdrsize = 0,
  55         .name = NETLBL_NLTYPE_CIPSOV4_NAME,
  56         .version = NETLBL_PROTO_VERSION,
  57         .maxattr = NLBL_CIPSOV4_A_MAX,
  58 };
  59
  60 /* NetLabel Netlink attribute policy */
  61 static struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = {
  62         [NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 },
  63         [NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 },
  64         [NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 },
  65         [NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED },
  66         [NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 },
  67         [NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 },
  68         [NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED },
  69         [NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED },
  70         [NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 },
  71         [NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 },
  72         [NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED },
  73         [NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED },
  74 };
  75
  76 /*
  77  * Helper Functions
  78  */
  79
  80 /**
  81  * netlbl_cipsov4_doi_free - Frees a CIPSO V4 DOI definition
  82  * @entry: the entry's RCU field
  83  *
  84  * Description:
  85  * This function is designed to be used as a callback to the call_rcu()
  86  * function so that the memory allocated to the DOI definition can be released
  87  * safely.
  88  *
  89  */
  90 static void netlbl_cipsov4_doi_free(struct rcu_head *entry)
  91 {
  92         struct cipso_v4_doi *ptr;
  93
  94         ptr = container_of(entry, struct cipso_v4_doi, rcu);
  95         switch (ptr->type) {
  96         case CIPSO_V4_MAP_STD:
  97                 kfree(ptr->map.std->lvl.cipso);
  98                 kfree(ptr->map.std->lvl.local);
  99                 kfree(ptr->map.std->cat.cipso);
 100                 kfree(ptr->map.std->cat.local);
 101                 break;
 102         }
 103         kfree(ptr);
 104 }
 105
 106 /**
 107  * netlbl_cipsov4_add_common - Parse the common sections of a ADD message
 108  * @info: the Generic NETLINK info block
 109  * @doi_def: the CIPSO V4 DOI definition
 110  *
 111  * Description:
 112  * Parse the common sections of a ADD message and fill in the related values
 113  * in @doi_def.  Returns zero on success, negative values on failure.
 114  *
 115  */
 116 static int netlbl_cipsov4_add_common(struct genl_info *info,
 117                                      struct cipso_v4_doi *doi_def)
 118 {
 119         struct nlattr *nla;
 120         int nla_rem;
 121         u32 iter = 0;
 122
 123         doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
 124
 125         if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_TAGLST],
 126                                 NLBL_CIPSOV4_A_MAX,
 127                                 netlbl_cipsov4_genl_policy) != 0)
 128                 return -EINVAL;
 129
 130         nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem)
 131                 if (nla->nla_type == NLBL_CIPSOV4_A_TAG) {
 132                         if (iter > CIPSO_V4_TAG_MAXCNT)
 133                                 return -EINVAL;
 134                         doi_def->tags[iter++] = nla_get_u8(nla);
 135                 }
 136         if (iter < CIPSO_V4_TAG_MAXCNT)
 137                 doi_def->tags[iter] = CIPSO_V4_TAG_INVALID;
 138
 139         return 0;
 140 }
 141
 142 /*
 143  * NetLabel Command Handlers
 144  */
 145
 146 /**
 147  * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition
 148  * @info: the Generic NETLINK info block
 149  *
 150  * Description:
 151  * Create a new CIPSO_V4_MAP_STD DOI definition based on the given ADD message
 152  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
 153  * error.
 154  *
 155  */
 156 static int netlbl_cipsov4_add_std(struct genl_info *info)
 157 {
 158         int ret_val = -EINVAL;
 159         struct cipso_v4_doi *doi_def = NULL;
 160         struct nlattr *nla_a;
 161         struct nlattr *nla_b;
 162         int nla_a_rem;
 163         int nla_b_rem;
 164
 165         if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
 166             !info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
 167             !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
 168                 return -EINVAL;
 169
 170         if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
 171                                 NLBL_CIPSOV4_A_MAX,
 172                                 netlbl_cipsov4_genl_policy) != 0)
 173                 return -EINVAL;
 174
 175         doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
 176         if (doi_def == NULL)
 177                 return -ENOMEM;
 178         doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL);
 179         if (doi_def->map.std == NULL) {
 180                 ret_val = -ENOMEM;
 181                 goto add_std_failure;
 182         }
 183         doi_def->type = CIPSO_V4_MAP_STD;
 184
 185         ret_val = netlbl_cipsov4_add_common(info, doi_def);
 186         if (ret_val != 0)
 187                 goto add_std_failure;
 188
 189         nla_for_each_nested(nla_a,
 190                             info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
 191                             nla_a_rem)
 192                 if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
 193                         nla_for_each_nested(nla_b, nla_a, nla_b_rem)
 194                                 switch (nla_b->nla_type) {
 195                                 case NLBL_CIPSOV4_A_MLSLVLLOC:
 196                                         if (nla_get_u32(nla_b) >=
 197                                             doi_def->map.std->lvl.local_size)
 198                                              doi_def->map.std->lvl.local_size =
 199                                                      nla_get_u32(nla_b) + 1;
 200                                         break;
 201                                 case NLBL_CIPSOV4_A_MLSLVLREM:
 202                                         if (nla_get_u32(nla_b) >=
 203                                             doi_def->map.std->lvl.cipso_size)
 204                                              doi_def->map.std->lvl.cipso_size =
 205                                                      nla_get_u32(nla_b) + 1;
 206                                         break;
 207                                 }
 208                 }
 209         if (doi_def->map.std->lvl.local_size > CIPSO_V4_MAX_LOC_LVLS ||
 210             doi_def->map.std->lvl.cipso_size > CIPSO_V4_MAX_REM_LVLS)
 211                 goto add_std_failure;
 212         doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
 213                                               sizeof(u32),
 214                                               GFP_KERNEL);
 215         if (doi_def->map.std->lvl.local == NULL) {
 216                 ret_val = -ENOMEM;
 217                 goto add_std_failure;
 218         }
 219         doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
 220                                               sizeof(u32),
 221                                               GFP_KERNEL);
 222         if (doi_def->map.std->lvl.cipso == NULL) {
 223                 ret_val = -ENOMEM;
 224                 goto add_std_failure;
 225         }
 226         nla_for_each_nested(nla_a,
 227                             info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
 228                             nla_a_rem)
 229                 if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
 230                         struct nlattr *lvl_loc;
 231                         struct nlattr *lvl_rem;
 232
 233                         if (nla_validate_nested(nla_a,
 234                                               NLBL_CIPSOV4_A_MAX,
 235                                               netlbl_cipsov4_genl_policy) != 0)
 236                                 goto add_std_failure;
 237
 238                         lvl_loc = nla_find_nested(nla_a,
 239                                                   NLBL_CIPSOV4_A_MLSLVLLOC);
 240                         lvl_rem = nla_find_nested(nla_a,
 241                                                   NLBL_CIPSOV4_A_MLSLVLREM);
 242                         if (lvl_loc == NULL || lvl_rem == NULL)
 243                                 goto add_std_failure;
 244                         doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] =
 245                                 nla_get_u32(lvl_rem);
 246                         doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] =
 247                                 nla_get_u32(lvl_loc);
 248                 }
 249
 250         if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) {
 251                 if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
 252                                         NLBL_CIPSOV4_A_MAX,
 253                                         netlbl_cipsov4_genl_policy) != 0)
 254                         goto add_std_failure;
 255
 256                 nla_for_each_nested(nla_a,
 257                                     info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
 258                                     nla_a_rem)
 259                         if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
 260                                 if (nla_validate_nested(nla_a,
 261                                               NLBL_CIPSOV4_A_MAX,
 262                                               netlbl_cipsov4_genl_policy) != 0)
 263                                         goto add_std_failure;
 264                                 nla_for_each_nested(nla_b, nla_a, nla_b_rem)
 265                                         switch (nla_b->nla_type) {
 266                                         case NLBL_CIPSOV4_A_MLSCATLOC:
 267                                                 if (nla_get_u32(nla_b) >=
 268                                               doi_def->map.std->cat.local_size)
 269                                              doi_def->map.std->cat.local_size =
 270                                                      nla_get_u32(nla_b) + 1;
 271                                                 break;
 272                                         case NLBL_CIPSOV4_A_MLSCATREM:
 273                                                 if (nla_get_u32(nla_b) >=
 274                                               doi_def->map.std->cat.cipso_size)
 275                                              doi_def->map.std->cat.cipso_size =
 276                                                      nla_get_u32(nla_b) + 1;
 277                                                 break;
 278                                         }
 279                         }
 280                 if (doi_def->map.std->cat.local_size > CIPSO_V4_MAX_LOC_CATS ||
 281                     doi_def->map.std->cat.cipso_size > CIPSO_V4_MAX_REM_CATS)
 282                         goto add_std_failure;
 283                 doi_def->map.std->cat.local = kcalloc(
 284                                               doi_def->map.std->cat.local_size,
 285                                               sizeof(u32),
 286                                               GFP_KERNEL);
 287                 if (doi_def->map.std->cat.local == NULL) {
 288                         ret_val = -ENOMEM;
 289                         goto add_std_failure;
 290                 }
 291                 doi_def->map.std->cat.cipso = kcalloc(
 292                                               doi_def->map.std->cat.cipso_size,
 293                                               sizeof(u32),
 294                                               GFP_KERNEL);
 295                 if (doi_def->map.std->cat.cipso == NULL) {
 296                         ret_val = -ENOMEM;
 297                         goto add_std_failure;
 298                 }
 299                 nla_for_each_nested(nla_a,
 300                                     info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
 301                                     nla_a_rem)
 302                         if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
 303                                 struct nlattr *cat_loc;
 304                                 struct nlattr *cat_rem;
 305
 306                                 cat_loc = nla_find_nested(nla_a,
 307                                                      NLBL_CIPSOV4_A_MLSCATLOC);
 308                                 cat_rem = nla_find_nested(nla_a,
 309                                                      NLBL_CIPSOV4_A_MLSCATREM);
 310                                 if (cat_loc == NULL || cat_rem == NULL)
 311                                         goto add_std_failure;
 312                                 doi_def->map.std->cat.local[
 313                                                         nla_get_u32(cat_loc)] =
 314                                         nla_get_u32(cat_rem);
 315                                 doi_def->map.std->cat.cipso[
 316                                                         nla_get_u32(cat_rem)] =
 317                                         nla_get_u32(cat_loc);
 318                         }
 319         }
 320
 321         ret_val = cipso_v4_doi_add(doi_def);
 322         if (ret_val != 0)
 323                 goto add_std_failure;
 324         return 0;
 325
 326 add_std_failure:
 327         if (doi_def)
 328                 netlbl_cipsov4_doi_free(&doi_def->rcu);
 329         return ret_val;
 330 }
 331
 332 /**
 333  * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition
 334  * @info: the Generic NETLINK info block
 335  *
 336  * Description:
 337  * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message
 338  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
 339  * error.
 340  *
 341  */
 342 static int netlbl_cipsov4_add_pass(struct genl_info *info)
 343 {
 344         int ret_val;
 345         struct cipso_v4_doi *doi_def = NULL;
 346
 347         if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
 348             !info->attrs[NLBL_CIPSOV4_A_TAGLST])
 349                 return -EINVAL;
 350
 351         doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
 352         if (doi_def == NULL)
 353                 return -ENOMEM;
 354         doi_def->type = CIPSO_V4_MAP_PASS;
 355
 356         ret_val = netlbl_cipsov4_add_common(info, doi_def);
 357         if (ret_val != 0)
 358                 goto add_pass_failure;
 359
 360         ret_val = cipso_v4_doi_add(doi_def);
 361         if (ret_val != 0)
 362                 goto add_pass_failure;
 363         return 0;
 364
 365 add_pass_failure:
 366         netlbl_cipsov4_doi_free(&doi_def->rcu);
 367         return ret_val;
 368 }
 369
 370 /**
 371  * netlbl_cipsov4_add - Handle an ADD message
 372  * @skb: the NETLINK buffer
 373  * @info: the Generic NETLINK info block
 374  *
 375  * Description:
 376  * Create a new DOI definition based on the given ADD message and add it to the
 377  * CIPSO V4 engine.  Returns zero on success, negative values on failure.
 378  *
 379  */
 380 static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
 381
 382 {
 383         int ret_val = -EINVAL;
 384         u32 map_type;
 385
 386         if (!info->attrs[NLBL_CIPSOV4_A_MTYPE])
 387                 return -EINVAL;
 388
 389         map_type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
 390         switch (map_type) {
 391         case CIPSO_V4_MAP_STD:
 392                 ret_val = netlbl_cipsov4_add_std(info);
 393                 break;
 394         case CIPSO_V4_MAP_PASS:
 395                 ret_val = netlbl_cipsov4_add_pass(info);
 396                 break;
 397         }
 398
 399         return ret_val;
 400 }
 401
 402 /**
 403  * netlbl_cipsov4_list - Handle a LIST message
 404  * @skb: the NETLINK buffer
 405  * @info: the Generic NETLINK info block
 406  *
 407  * Description:
 408  * Process a user generated LIST message and respond accordingly.  While the
 409  * response message generated by the kernel is straightforward, determining
 410  * before hand the size of the buffer to allocate is not (we have to generate
 411  * the message to know the size).  In order to keep this function sane what we
 412  * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in
 413  * that size, if we fail then we restart with a larger buffer and try again.
 414  * We continue in this manner until we hit a limit of failed attempts then we
 415  * give up and just send an error message.  Returns zero on success and
 416  * negative values on error.
 417  *
 418  */
 419 static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info)
 420 {
 421         int ret_val;
 422         struct sk_buff *ans_skb = NULL;
 423         u32 nlsze_mult = 1;
 424         void *data;
 425         u32 doi;
 426         struct nlattr *nla_a;
 427         struct nlattr *nla_b;
 428         struct cipso_v4_doi *doi_def;
 429         u32 iter;
 430
 431         if (!info->attrs[NLBL_CIPSOV4_A_DOI]) {
 432                 ret_val = -EINVAL;
 433                 goto list_failure;
 434         }
 435
 436 list_start:
 437         ans_skb = nlmsg_new(NLMSG_GOODSIZE * nlsze_mult, GFP_KERNEL);
 438         if (ans_skb == NULL) {
 439                 ret_val = -ENOMEM;
 440                 goto list_failure;
 441         }
 442         data = netlbl_netlink_hdr_put(ans_skb,
 443                                       info->snd_pid,
 444                                       info->snd_seq,
 445                                       netlbl_cipsov4_gnl_family.id,
 446                                       0,
 447                                       NLBL_CIPSOV4_C_LIST);
 448         if (data == NULL) {
 449                 ret_val = -ENOMEM;
 450                 goto list_failure;
 451         }
 452
 453         doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
 454
 455         rcu_read_lock();
 456         doi_def = cipso_v4_doi_getdef(doi);
 457         if (doi_def == NULL) {
 458                 ret_val = -EINVAL;
 459                 goto list_failure;
 460         }
 461
 462         ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type);
 463         if (ret_val != 0)
 464                 goto list_failure_lock;
 465
 466         nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_TAGLST);
 467         if (nla_a == NULL) {
 468                 ret_val = -ENOMEM;
 469                 goto list_failure_lock;
 470         }
 471         for (iter = 0;
 472              iter < CIPSO_V4_TAG_MAXCNT &&
 473                doi_def->tags[iter] != CIPSO_V4_TAG_INVALID;
 474              iter++) {
 475                 ret_val = nla_put_u8(ans_skb,
 476                                      NLBL_CIPSOV4_A_TAG,
 477                                      doi_def->tags[iter]);
 478                 if (ret_val != 0)
 479                         goto list_failure_lock;
 480         }
 481         nla_nest_end(ans_skb, nla_a);
 482
 483         switch (doi_def->type) {
 484         case CIPSO_V4_MAP_STD:
 485                 nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVLLST);
 486                 if (nla_a == NULL) {
 487                         ret_val = -ENOMEM;
 488                         goto list_failure_lock;
 489                 }
 490                 for (iter = 0;
 491                      iter < doi_def->map.std->lvl.local_size;
 492                      iter++) {
 493                         if (doi_def->map.std->lvl.local[iter] ==
 494                             CIPSO_V4_INV_LVL)
 495                                 continue;
 496
 497                         nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVL);
 498                         if (nla_b == NULL) {
 499                                 ret_val = -ENOMEM;
 500                                 goto list_retry;
 501                         }
 502                         ret_val = nla_put_u32(ans_skb,
 503                                               NLBL_CIPSOV4_A_MLSLVLLOC,
 504                                               iter);
 505                         if (ret_val != 0)
 506                                 goto list_retry;
 507                         ret_val = nla_put_u32(ans_skb,
 508                                             NLBL_CIPSOV4_A_MLSLVLREM,
 509                                             doi_def->map.std->lvl.local[iter]);
 510                         if (ret_val != 0)
 511                                 goto list_retry;
 512                         nla_nest_end(ans_skb, nla_b);
 513                 }
 514                 nla_nest_end(ans_skb, nla_a);
 515
 516                 nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCATLST);
 517                 if (nla_a == NULL) {
 518                         ret_val = -ENOMEM;
 519                         goto list_retry;
 520                 }
 521                 for (iter = 0;
 522                      iter < doi_def->map.std->cat.local_size;
 523                      iter++) {
 524                         if (doi_def->map.std->cat.local[iter] ==
 525                             CIPSO_V4_INV_CAT)
 526                                 continue;
 527
 528                         nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCAT);
 529                         if (nla_b == NULL) {
 530                                 ret_val = -ENOMEM;
 531                                 goto list_retry;
 532                         }
 533                         ret_val = nla_put_u32(ans_skb,
 534                                               NLBL_CIPSOV4_A_MLSCATLOC,
 535                                               iter);
 536                         if (ret_val != 0)
 537                                 goto list_retry;
 538                         ret_val = nla_put_u32(ans_skb,
 539                                             NLBL_CIPSOV4_A_MLSCATREM,
 540                                             doi_def->map.std->cat.local[iter]);
 541                         if (ret_val != 0)
 542                                 goto list_retry;
 543                         nla_nest_end(ans_skb, nla_b);
 544                 }
 545                 nla_nest_end(ans_skb, nla_a);
 546
 547                 break;
 548         }
 549         rcu_read_unlock();
 550
 551         genlmsg_end(ans_skb, data);
 552
 553         ret_val = genlmsg_unicast(ans_skb, info->snd_pid);
 554         if (ret_val != 0)
 555                 goto list_failure;
 556
 557         return 0;
 558
 559 list_retry:
 560         /* XXX - this limit is a guesstimate */
 561         if (nlsze_mult < 4) {
 562                 rcu_read_unlock();
 563                 kfree_skb(ans_skb);
 564                 nlsze_mult++;
 565                 goto list_start;
 566         }
 567 list_failure_lock:
 568         rcu_read_unlock();
 569 list_failure:
 570         kfree_skb(ans_skb);
 571         return ret_val;
 572 }
 573
 574 /**
 575  * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL
 576  * @doi_def: the CIPSOv4 DOI definition
 577  * @arg: the netlbl_cipsov4_doiwalk_arg structure
 578  *
 579  * Description:
 580  * This function is designed to be used as a callback to the
 581  * cipso_v4_doi_walk() function for use in generating a response for a LISTALL
 582  * message.  Returns the size of the message on success, negative values on
 583  * failure.
 584  *
 585  */
 586 static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg)
 587 {
 588         int ret_val = -ENOMEM;
 589         struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg;
 590         void *data;
 591
 592         data = netlbl_netlink_hdr_put(cb_arg->skb,
 593                                       NETLINK_CB(cb_arg->nl_cb->skb).pid,
 594                                       cb_arg->seq,
 595                                       netlbl_cipsov4_gnl_family.id,
 596                                       NLM_F_MULTI,
 597                                       NLBL_CIPSOV4_C_LISTALL);
 598         if (data == NULL)
 599                 goto listall_cb_failure;
 600
 601         ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi);
 602         if (ret_val != 0)
 603                 goto listall_cb_failure;
 604         ret_val = nla_put_u32(cb_arg->skb,
 605                               NLBL_CIPSOV4_A_MTYPE,
 606                               doi_def->type);
 607         if (ret_val != 0)
 608                 goto listall_cb_failure;
 609
 610         return genlmsg_end(cb_arg->skb, data);
 611
 612 listall_cb_failure:
 613         genlmsg_cancel(cb_arg->skb, data);
 614         return ret_val;
 615 }
 616
 617 /**
 618  * netlbl_cipsov4_listall - Handle a LISTALL message
 619  * @skb: the NETLINK buffer
 620  * @cb: the NETLINK callback
 621  *
 622  * Description:
 623  * Process a user generated LISTALL message and respond accordingly.  Returns
 624  * zero on success and negative values on error.
 625  *
 626  */
 627 static int netlbl_cipsov4_listall(struct sk_buff *skb,
 628                                   struct netlink_callback *cb)
 629 {
 630         struct netlbl_cipsov4_doiwalk_arg cb_arg;
 631         int doi_skip = cb->args[0];
 632
 633         cb_arg.nl_cb = cb;
 634         cb_arg.skb = skb;
 635         cb_arg.seq = cb->nlh->nlmsg_seq;
 636
 637         cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg);
 638
 639         cb->args[0] = doi_skip;
 640         return skb->len;
 641 }
 642
 643 /**
 644  * netlbl_cipsov4_remove - Handle a REMOVE message
 645  * @skb: the NETLINK buffer
 646  * @info: the Generic NETLINK info block
 647  *
 648  * Description:
 649  * Process a user generated REMOVE message and respond accordingly.  Returns
 650  * zero on success, negative values on failure.
 651  *
 652  */
 653 static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
 654 {
 655         int ret_val = -EINVAL;
 656         u32 doi;
 657
 658         if (info->attrs[NLBL_CIPSOV4_A_DOI]) {
 659                 doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
 660                 ret_val = cipso_v4_doi_remove(doi, netlbl_cipsov4_doi_free);
 661         }
 662
 663         return ret_val;
 664 }
 665
 666 /*
 667  * NetLabel Generic NETLINK Command Definitions
 668  */
 669
 670 static struct genl_ops netlbl_cipsov4_genl_c_add = {
 671         .cmd = NLBL_CIPSOV4_C_ADD,
 672         .flags = GENL_ADMIN_PERM,
 673         .policy = netlbl_cipsov4_genl_policy,
 674         .doit = netlbl_cipsov4_add,
 675         .dumpit = NULL,
 676 };
 677
 678 static struct genl_ops netlbl_cipsov4_genl_c_remove = {
 679         .cmd = NLBL_CIPSOV4_C_REMOVE,
 680         .flags = GENL_ADMIN_PERM,
 681         .policy = netlbl_cipsov4_genl_policy,
 682         .doit = netlbl_cipsov4_remove,
 683         .dumpit = NULL,
 684 };
 685
 686 static struct genl_ops netlbl_cipsov4_genl_c_list = {
 687         .cmd = NLBL_CIPSOV4_C_LIST,
 688         .flags = 0,
 689         .policy = netlbl_cipsov4_genl_policy,
 690         .doit = netlbl_cipsov4_list,
 691         .dumpit = NULL,
 692 };
 693
 694 static struct genl_ops netlbl_cipsov4_genl_c_listall = {
 695         .cmd = NLBL_CIPSOV4_C_LISTALL,
 696         .flags = 0,
 697         .policy = netlbl_cipsov4_genl_policy,
 698         .doit = NULL,
 699         .dumpit = netlbl_cipsov4_listall,
 700 };
 701
 702 /*
 703  * NetLabel Generic NETLINK Protocol Functions
 704  */
 705
 706 /**
 707  * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component
 708  *
 709  * Description:
 710  * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK
 711  * mechanism.  Returns zero on success, negative values on failure.
 712  *
 713  */
 714 int netlbl_cipsov4_genl_init(void)
 715 {
 716         int ret_val;
 717
 718         ret_val = genl_register_family(&netlbl_cipsov4_gnl_family);
 719         if (ret_val != 0)
 720                 return ret_val;
 721
 722         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
 723                                     &netlbl_cipsov4_genl_c_add);
 724         if (ret_val != 0)
 725                 return ret_val;
 726         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
 727                                     &netlbl_cipsov4_genl_c_remove);
 728         if (ret_val != 0)
 729                 return ret_val;
 730         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
 731                                     &netlbl_cipsov4_genl_c_list);
 732         if (ret_val != 0)
 733                 return ret_val;
 734         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
 735                                     &netlbl_cipsov4_genl_c_listall);
 736         if (ret_val != 0)
 737                 return ret_val;
 738
 739         return 0;
 740 }