net/netlabel/netlabel_kapi.c

   1 /*
   2  * NetLabel Kernel API
   3  *
   4  * This file defines the kernel API for the NetLabel system.  The NetLabel
   5  * system manages static and dynamic label mappings for network protocols such
   6  * 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, 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/init.h>
  32 #include <linux/types.h>
  33 #include <linux/audit.h>
  34 #include <linux/in.h>
  35 #include <linux/in6.h>
  36 #include <net/ip.h>
  37 #include <net/ipv6.h>
  38 #include <net/netlabel.h>
  39 #include <net/cipso_ipv4.h>
  40 #include <asm/bug.h>
  41 #include <asm/atomic.h>
  42
  43 #include "netlabel_domainhash.h"
  44 #include "netlabel_unlabeled.h"
  45 #include "netlabel_cipso_v4.h"
  46 #include "netlabel_user.h"
  47 #include "netlabel_mgmt.h"
  48 #include "netlabel_addrlist.h"
  49
  50 /*
  51  * Configuration Functions
  52  */
  53
  54 /**
  55  * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping
  56  * @domain: the domain mapping to remove
  57  * @family: address family
  58  * @addr: IP address
  59  * @mask: IP address mask
  60  * @audit_info: NetLabel audit information
  61  *
  62  * Description:
  63  * Removes a NetLabel/LSM domain mapping.  A @domain value of NULL causes the
  64  * default domain mapping to be removed.  Returns zero on success, negative
  65  * values on failure.
  66  *
  67  */
  68 int netlbl_cfg_map_del(const char *domain,
  69                        u16 family,
  70                        const void *addr,
  71                        const void *mask,
  72                        struct netlbl_audit *audit_info)
  73 {
  74         if (addr == NULL && mask == NULL) {
  75                 return netlbl_domhsh_remove(domain, audit_info);
  76         } else if (addr != NULL && mask != NULL) {
  77                 switch (family) {
  78                 case AF_INET:
  79                         return netlbl_domhsh_remove_af4(domain, addr, mask,
  80                                                         audit_info);
  81                 default:
  82                         return -EPFNOSUPPORT;
  83                 }
  84         } else
  85                 return -EINVAL;
  86 }
  87
  88 /**
  89  * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping
  90  * @domain: the domain mapping to add
  91  * @family: address family
  92  * @addr: IP address
  93  * @mask: IP address mask
  94  * @audit_info: NetLabel audit information
  95  *
  96  * Description:
  97  * Adds a new unlabeled NetLabel/LSM domain mapping.  A @domain value of NULL
  98  * causes a new default domain mapping to be added.  Returns zero on success,
  99  * negative values on failure.
 100  *
 101  */
 102 int netlbl_cfg_unlbl_map_add(const char *domain,
 103                              u16 family,
 104                              const void *addr,
 105                              const void *mask,
 106                              struct netlbl_audit *audit_info)
 107 {
 108         int ret_val = -ENOMEM;
 109         struct netlbl_dom_map *entry;
 110         struct netlbl_domaddr_map *addrmap = NULL;
 111         struct netlbl_domaddr4_map *map4 = NULL;
 112         struct netlbl_domaddr6_map *map6 = NULL;
 113         const struct in_addr *addr4, *mask4;
 114         const struct in6_addr *addr6, *mask6;
 115
 116         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 117         if (entry == NULL)
 118                 return -ENOMEM;
 119         if (domain != NULL) {
 120                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 121                 if (entry->domain == NULL)
 122                         goto cfg_unlbl_map_add_failure;
 123         }
 124
 125         if (addr == NULL && mask == NULL)
 126                 entry->type = NETLBL_NLTYPE_UNLABELED;
 127         else if (addr != NULL && mask != NULL) {
 128                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 129                 if (addrmap == NULL)
 130                         goto cfg_unlbl_map_add_failure;
 131                 INIT_LIST_HEAD(&addrmap->list4);
 132                 INIT_LIST_HEAD(&addrmap->list6);
 133
 134                 switch (family) {
 135                 case AF_INET:
 136                         addr4 = addr;
 137                         mask4 = mask;
 138                         map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
 139                         if (map4 == NULL)
 140                                 goto cfg_unlbl_map_add_failure;
 141                         map4->type = NETLBL_NLTYPE_UNLABELED;
 142                         map4->list.addr = addr4->s_addr & mask4->s_addr;
 143                         map4->list.mask = mask4->s_addr;
 144                         map4->list.valid = 1;
 145                         ret_val = netlbl_af4list_add(&map4->list,
 146                                                      &addrmap->list4);
 147                         if (ret_val != 0)
 148                                 goto cfg_unlbl_map_add_failure;
 149                         break;
 150                 case AF_INET6:
 151                         addr6 = addr;
 152                         mask6 = mask;
 153                         map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
 154                         if (map6 == NULL)
 155                                 goto cfg_unlbl_map_add_failure;
 156                         map6->type = NETLBL_NLTYPE_UNLABELED;
 157                         ipv6_addr_copy(&map6->list.addr, addr6);
 158                         map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
 159                         map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
 160                         map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
 161                         map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
 162                         ipv6_addr_copy(&map6->list.mask, mask6);
 163                         map6->list.valid = 1;
 164                         ret_val = netlbl_af4list_add(&map4->list,
 165                                                      &addrmap->list4);
 166                         if (ret_val != 0)
 167                                 goto cfg_unlbl_map_add_failure;
 168                         break;
 169                 default:
 170                         goto cfg_unlbl_map_add_failure;
 171                         break;
 172                 }
 173
 174                 entry->type_def.addrsel = addrmap;
 175                 entry->type = NETLBL_NLTYPE_ADDRSELECT;
 176         } else {
 177                 ret_val = -EINVAL;
 178                 goto cfg_unlbl_map_add_failure;
 179         }
 180
 181         ret_val = netlbl_domhsh_add(entry, audit_info);
 182         if (ret_val != 0)
 183                 goto cfg_unlbl_map_add_failure;
 184
 185         return 0;
 186
 187 cfg_unlbl_map_add_failure:
 188         if (entry != NULL)
 189                 kfree(entry->domain);
 190         kfree(entry);
 191         kfree(addrmap);
 192         kfree(map4);
 193         kfree(map6);
 194         return ret_val;
 195 }
 196
 197
 198 /**
 199  * netlbl_cfg_unlbl_static_add - Adds a new static label
 200  * @net: network namespace
 201  * @dev_name: interface name
 202  * @addr: IP address in network byte order (struct in[6]_addr)
 203  * @mask: address mask in network byte order (struct in[6]_addr)
 204  * @family: address family
 205  * @secid: LSM secid value for the entry
 206  * @audit_info: NetLabel audit information
 207  *
 208  * Description:
 209  * Adds a new NetLabel static label to be used when protocol provided labels
 210  * are not present on incoming traffic.  If @dev_name is NULL then the default
 211  * interface will be used.  Returns zero on success, negative values on failure.
 212  *
 213  */
 214 int netlbl_cfg_unlbl_static_add(struct net *net,
 215                                 const char *dev_name,
 216                                 const void *addr,
 217                                 const void *mask,
 218                                 u16 family,
 219                                 u32 secid,
 220                                 struct netlbl_audit *audit_info)
 221 {
 222         u32 addr_len;
 223
 224         switch (family) {
 225         case AF_INET:
 226                 addr_len = sizeof(struct in_addr);
 227                 break;
 228         case AF_INET6:
 229                 addr_len = sizeof(struct in6_addr);
 230                 break;
 231         default:
 232                 return -EPFNOSUPPORT;
 233         }
 234
 235         return netlbl_unlhsh_add(net,
 236                                  dev_name, addr, mask, addr_len,
 237                                  secid, audit_info);
 238 }
 239
 240 /**
 241  * netlbl_cfg_unlbl_static_del - Removes an existing static label
 242  * @net: network namespace
 243  * @dev_name: interface name
 244  * @addr: IP address in network byte order (struct in[6]_addr)
 245  * @mask: address mask in network byte order (struct in[6]_addr)
 246  * @family: address family
 247  * @secid: LSM secid value for the entry
 248  * @audit_info: NetLabel audit information
 249  *
 250  * Description:
 251  * Removes an existing NetLabel static label used when protocol provided labels
 252  * are not present on incoming traffic.  If @dev_name is NULL then the default
 253  * interface will be used.  Returns zero on success, negative values on failure.
 254  *
 255  */
 256 int netlbl_cfg_unlbl_static_del(struct net *net,
 257                                 const char *dev_name,
 258                                 const void *addr,
 259                                 const void *mask,
 260                                 u16 family,
 261                                 struct netlbl_audit *audit_info)
 262 {
 263         u32 addr_len;
 264
 265         switch (family) {
 266         case AF_INET:
 267                 addr_len = sizeof(struct in_addr);
 268                 break;
 269         case AF_INET6:
 270                 addr_len = sizeof(struct in6_addr);
 271                 break;
 272         default:
 273                 return -EPFNOSUPPORT;
 274         }
 275
 276         return netlbl_unlhsh_remove(net,
 277                                     dev_name, addr, mask, addr_len,
 278                                     audit_info);
 279 }
 280
 281 /**
 282  * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition
 283  * @doi_def: CIPSO DOI definition
 284  * @audit_info: NetLabel audit information
 285  *
 286  * Description:
 287  * Add a new CIPSO DOI definition as defined by @doi_def.  Returns zero on
 288  * success and negative values on failure.
 289  *
 290  */
 291 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
 292                            struct netlbl_audit *audit_info)
 293 {
 294         return cipso_v4_doi_add(doi_def, audit_info);
 295 }
 296
 297 /**
 298  * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition
 299  * @doi: CIPSO DOI
 300  * @audit_info: NetLabel audit information
 301  *
 302  * Description:
 303  * Remove an existing CIPSO DOI definition matching @doi.  Returns zero on
 304  * success and negative values on failure.
 305  *
 306  */
 307 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info)
 308 {
 309         cipso_v4_doi_remove(doi, audit_info);
 310 }
 311
 312 /**
 313  * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping
 314  * @doi: the CIPSO DOI
 315  * @domain: the domain mapping to add
 316  * @addr: IP address
 317  * @mask: IP address mask
 318  * @audit_info: NetLabel audit information
 319  *
 320  * Description:
 321  * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel
 322  * subsystem.  A @domain value of NULL adds a new default domain mapping.
 323  * Returns zero on success, negative values on failure.
 324  *
 325  */
 326 int netlbl_cfg_cipsov4_map_add(u32 doi,
 327                                const char *domain,
 328                                const struct in_addr *addr,
 329                                const struct in_addr *mask,
 330                                struct netlbl_audit *audit_info)
 331 {
 332         int ret_val = -ENOMEM;
 333         struct cipso_v4_doi *doi_def;
 334         struct netlbl_dom_map *entry;
 335         struct netlbl_domaddr_map *addrmap = NULL;
 336         struct netlbl_domaddr4_map *addrinfo = NULL;
 337
 338         doi_def = cipso_v4_doi_getdef(doi);
 339         if (doi_def == NULL)
 340                 return -ENOENT;
 341
 342         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 343         if (entry == NULL)
 344                 return -ENOMEM;
 345         if (domain != NULL) {
 346                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 347                 if (entry->domain == NULL)
 348                         goto cfg_cipsov4_map_add_failure;
 349         }
 350
 351         if (addr == NULL && mask == NULL) {
 352                 entry->type_def.cipsov4 = doi_def;
 353                 entry->type = NETLBL_NLTYPE_CIPSOV4;
 354         } else if (addr != NULL && mask != NULL) {
 355                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 356                 if (addrmap == NULL)
 357                         goto cfg_cipsov4_map_add_failure;
 358                 INIT_LIST_HEAD(&addrmap->list4);
 359                 INIT_LIST_HEAD(&addrmap->list6);
 360
 361                 addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC);
 362                 if (addrinfo == NULL)
 363                         goto cfg_cipsov4_map_add_failure;
 364                 addrinfo->type_def.cipsov4 = doi_def;
 365                 addrinfo->type = NETLBL_NLTYPE_CIPSOV4;
 366                 addrinfo->list.addr = addr->s_addr & mask->s_addr;
 367                 addrinfo->list.mask = mask->s_addr;
 368                 addrinfo->list.valid = 1;
 369                 ret_val = netlbl_af4list_add(&addrinfo->list, &addrmap->list4);
 370                 if (ret_val != 0)
 371                         goto cfg_cipsov4_map_add_failure;
 372
 373                 entry->type_def.addrsel = addrmap;
 374                 entry->type = NETLBL_NLTYPE_ADDRSELECT;
 375         } else {
 376                 ret_val = -EINVAL;
 377                 goto cfg_cipsov4_map_add_failure;
 378         }
 379
 380         ret_val = netlbl_domhsh_add(entry, audit_info);
 381         if (ret_val != 0)
 382                 goto cfg_cipsov4_map_add_failure;
 383
 384         return 0;
 385
 386 cfg_cipsov4_map_add_failure:
 387         cipso_v4_doi_putdef(doi_def);
 388         if (entry != NULL)
 389                 kfree(entry->domain);
 390         kfree(entry);
 391         kfree(addrmap);
 392         kfree(addrinfo);
 393         return ret_val;
 394 }
 395
 396 /*
 397  * Security Attribute Functions
 398  */
 399
 400 /**
 401  * netlbl_secattr_catmap_walk - Walk a LSM secattr catmap looking for a bit
 402  * @catmap: the category bitmap
 403  * @offset: the offset to start searching at, in bits
 404  *
 405  * Description:
 406  * This function walks a LSM secattr category bitmap starting at @offset and
 407  * returns the spot of the first set bit or -ENOENT if no bits are set.
 408  *
 409  */
 410 int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
 411                                u32 offset)
 412 {
 413         struct netlbl_lsm_secattr_catmap *iter = catmap;
 414         u32 node_idx;
 415         u32 node_bit;
 416         NETLBL_CATMAP_MAPTYPE bitmap;
 417
 418         if (offset > iter->startbit) {
 419                 while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 420                         iter = iter->next;
 421                         if (iter == NULL)
 422                                 return -ENOENT;
 423                 }
 424                 node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 425                 node_bit = offset - iter->startbit -
 426                            (NETLBL_CATMAP_MAPSIZE * node_idx);
 427         } else {
 428                 node_idx = 0;
 429                 node_bit = 0;
 430         }
 431         bitmap = iter->bitmap[node_idx] >> node_bit;
 432
 433         for (;;) {
 434                 if (bitmap != 0) {
 435                         while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
 436                                 bitmap >>= 1;
 437                                 node_bit++;
 438                         }
 439                         return iter->startbit +
 440                                 (NETLBL_CATMAP_MAPSIZE * node_idx) + node_bit;
 441                 }
 442                 if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
 443                         if (iter->next != NULL) {
 444                                 iter = iter->next;
 445                                 node_idx = 0;
 446                         } else
 447                                 return -ENOENT;
 448                 }
 449                 bitmap = iter->bitmap[node_idx];
 450                 node_bit = 0;
 451         }
 452
 453         return -ENOENT;
 454 }
 455
 456 /**
 457  * netlbl_secattr_catmap_walk_rng - Find the end of a string of set bits
 458  * @catmap: the category bitmap
 459  * @offset: the offset to start searching at, in bits
 460  *
 461  * Description:
 462  * This function walks a LSM secattr category bitmap starting at @offset and
 463  * returns the spot of the first cleared bit or -ENOENT if the offset is past
 464  * the end of the bitmap.
 465  *
 466  */
 467 int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
 468                                    u32 offset)
 469 {
 470         struct netlbl_lsm_secattr_catmap *iter = catmap;
 471         u32 node_idx;
 472         u32 node_bit;
 473         NETLBL_CATMAP_MAPTYPE bitmask;
 474         NETLBL_CATMAP_MAPTYPE bitmap;
 475
 476         if (offset > iter->startbit) {
 477                 while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 478                         iter = iter->next;
 479                         if (iter == NULL)
 480                                 return -ENOENT;
 481                 }
 482                 node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 483                 node_bit = offset - iter->startbit -
 484                            (NETLBL_CATMAP_MAPSIZE * node_idx);
 485         } else {
 486                 node_idx = 0;
 487                 node_bit = 0;
 488         }
 489         bitmask = NETLBL_CATMAP_BIT << node_bit;
 490
 491         for (;;) {
 492                 bitmap = iter->bitmap[node_idx];
 493                 while (bitmask != 0 && (bitmap & bitmask) != 0) {
 494                         bitmask <<= 1;
 495                         node_bit++;
 496                 }
 497
 498                 if (bitmask != 0)
 499                         return iter->startbit +
 500                                 (NETLBL_CATMAP_MAPSIZE * node_idx) +
 501                                 node_bit - 1;
 502                 else if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
 503                         if (iter->next == NULL)
 504                                 return iter->startbit + NETLBL_CATMAP_SIZE - 1;
 505                         iter = iter->next;
 506                         node_idx = 0;
 507                 }
 508                 bitmask = NETLBL_CATMAP_BIT;
 509                 node_bit = 0;
 510         }
 511
 512         return -ENOENT;
 513 }
 514
 515 /**
 516  * netlbl_secattr_catmap_setbit - Set a bit in a LSM secattr catmap
 517  * @catmap: the category bitmap
 518  * @bit: the bit to set
 519  * @flags: memory allocation flags
 520  *
 521  * Description:
 522  * Set the bit specified by @bit in @catmap.  Returns zero on success,
 523  * negative values on failure.
 524  *
 525  */
 526 int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
 527                                  u32 bit,
 528                                  gfp_t flags)
 529 {
 530         struct netlbl_lsm_secattr_catmap *iter = catmap;
 531         u32 node_bit;
 532         u32 node_idx;
 533
 534         while (iter->next != NULL &&
 535                bit >= (iter->startbit + NETLBL_CATMAP_SIZE))
 536                 iter = iter->next;
 537         if (bit >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 538                 iter->next = netlbl_secattr_catmap_alloc(flags);
 539                 if (iter->next == NULL)
 540                         return -ENOMEM;
 541                 iter = iter->next;
 542                 iter->startbit = bit & ~(NETLBL_CATMAP_SIZE - 1);
 543         }
 544
 545         /* gcc always rounds to zero when doing integer division */
 546         node_idx = (bit - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 547         node_bit = bit - iter->startbit - (NETLBL_CATMAP_MAPSIZE * node_idx);
 548         iter->bitmap[node_idx] |= NETLBL_CATMAP_BIT << node_bit;
 549
 550         return 0;
 551 }
 552
 553 /**
 554  * netlbl_secattr_catmap_setrng - Set a range of bits in a LSM secattr catmap
 555  * @catmap: the category bitmap
 556  * @start: the starting bit
 557  * @end: the last bit in the string
 558  * @flags: memory allocation flags
 559  *
 560  * Description:
 561  * Set a range of bits, starting at @start and ending with @end.  Returns zero
 562  * on success, negative values on failure.
 563  *
 564  */
 565 int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
 566                                  u32 start,
 567                                  u32 end,
 568                                  gfp_t flags)
 569 {
 570         int ret_val = 0;
 571         struct netlbl_lsm_secattr_catmap *iter = catmap;
 572         u32 iter_max_spot;
 573         u32 spot;
 574
 575         /* XXX - This could probably be made a bit faster by combining writes
 576          * to the catmap instead of setting a single bit each time, but for
 577          * right now skipping to the start of the range in the catmap should
 578          * be a nice improvement over calling the individual setbit function
 579          * repeatedly from a loop. */
 580
 581         while (iter->next != NULL &&
 582                start >= (iter->startbit + NETLBL_CATMAP_SIZE))
 583                 iter = iter->next;
 584         iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
 585
 586         for (spot = start; spot <= end && ret_val == 0; spot++) {
 587                 if (spot >= iter_max_spot && iter->next != NULL) {
 588                         iter = iter->next;
 589                         iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
 590                 }
 591                 ret_val = netlbl_secattr_catmap_setbit(iter, spot, GFP_ATOMIC);
 592         }
 593
 594         return ret_val;
 595 }
 596
 597 /*
 598  * LSM Functions
 599  */
 600
 601 /**
 602  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
 603  *
 604  * Description:
 605  * The LSM can use this function to determine if it should use NetLabel
 606  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
 607  * considered to be enabled when it's configuration contains a valid setup for
 608  * at least one labeled protocol (i.e. NetLabel can understand incoming
 609  * labeled packets of at least one type); otherwise NetLabel is considered to
 610  * be disabled.
 611  *
 612  */
 613 int netlbl_enabled(void)
 614 {
 615         /* At some point we probably want to expose this mechanism to the user
 616          * as well so that admins can toggle NetLabel regardless of the
 617          * configuration */
 618         return (atomic_read(&netlabel_mgmt_protocount) > 0);
 619 }
 620
 621 /**
 622  * netlbl_sock_setattr - Label a socket using the correct protocol
 623  * @sk: the socket to label
 624  * @family: protocol family
 625  * @secattr: the security attributes
 626  *
 627  * Description:
 628  * Attach the correct label to the given socket using the security attributes
 629  * specified in @secattr.  This function requires exclusive access to @sk,
 630  * which means it either needs to be in the process of being created or locked.
 631  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
 632  * network address selectors (can't blindly label the socket), and negative
 633  * values on all other failures.
 634  *
 635  */
 636 int netlbl_sock_setattr(struct sock *sk,
 637                         u16 family,
 638                         const struct netlbl_lsm_secattr *secattr)
 639 {
 640         int ret_val;
 641         struct netlbl_dom_map *dom_entry;
 642
 643         rcu_read_lock();
 644         dom_entry = netlbl_domhsh_getentry(secattr->domain);
 645         if (dom_entry == NULL) {
 646                 ret_val = -ENOENT;
 647                 goto socket_setattr_return;
 648         }
 649         switch (family) {
 650         case AF_INET:
 651                 switch (dom_entry->type) {
 652                 case NETLBL_NLTYPE_ADDRSELECT:
 653                         ret_val = -EDESTADDRREQ;
 654                         break;
 655                 case NETLBL_NLTYPE_CIPSOV4:
 656                         ret_val = cipso_v4_sock_setattr(sk,
 657                                                     dom_entry->type_def.cipsov4,
 658                                                     secattr);
 659                         break;
 660                 case NETLBL_NLTYPE_UNLABELED:
 661                         ret_val = 0;
 662                         break;
 663                 default:
 664                         ret_val = -ENOENT;
 665                 }
 666                 break;
 667 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 668         case AF_INET6:
 669                 /* since we don't support any IPv6 labeling protocols right
 670                  * now we can optimize everything away until we do */
 671                 ret_val = 0;
 672                 break;
 673 #endif /* IPv6 */
 674         default:
 675                 ret_val = -EPROTONOSUPPORT;
 676         }
 677
 678 socket_setattr_return:
 679         rcu_read_unlock();
 680         return ret_val;
 681 }
 682
 683 /**
 684  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
 685  * @sk: the socket
 686  *
 687  * Description:
 688  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
 689  * ensuring that @sk is locked.
 690  *
 691  */
 692 void netlbl_sock_delattr(struct sock *sk)
 693 {
 694         cipso_v4_sock_delattr(sk);
 695 }
 696
 697 /**
 698  * netlbl_sock_getattr - Determine the security attributes of a sock
 699  * @sk: the sock
 700  * @secattr: the security attributes
 701  *
 702  * Description:
 703  * Examines the given sock to see if any NetLabel style labeling has been
 704  * applied to the sock, if so it parses the socket label and returns the
 705  * security attributes in @secattr.  Returns zero on success, negative values
 706  * on failure.
 707  *
 708  */
 709 int netlbl_sock_getattr(struct sock *sk,
 710                         struct netlbl_lsm_secattr *secattr)
 711 {
 712         int ret_val;
 713
 714         switch (sk->sk_family) {
 715         case AF_INET:
 716                 ret_val = cipso_v4_sock_getattr(sk, secattr);
 717                 break;
 718 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 719         case AF_INET6:
 720                 ret_val = -ENOMSG;
 721                 break;
 722 #endif /* IPv6 */
 723         default:
 724                 ret_val = -EPROTONOSUPPORT;
 725         }
 726
 727         return ret_val;
 728 }
 729
 730 /**
 731  * netlbl_conn_setattr - Label a connected socket using the correct protocol
 732  * @sk: the socket to label
 733  * @addr: the destination address
 734  * @secattr: the security attributes
 735  *
 736  * Description:
 737  * Attach the correct label to the given connected socket using the security
 738  * attributes specified in @secattr.  The caller is responsible for ensuring
 739  * that @sk is locked.  Returns zero on success, negative values on failure.
 740  *
 741  */
 742 int netlbl_conn_setattr(struct sock *sk,
 743                         struct sockaddr *addr,
 744                         const struct netlbl_lsm_secattr *secattr)
 745 {
 746         int ret_val;
 747         struct sockaddr_in *addr4;
 748         struct netlbl_domaddr4_map *af4_entry;
 749
 750         rcu_read_lock();
 751         switch (addr->sa_family) {
 752         case AF_INET:
 753                 addr4 = (struct sockaddr_in *)addr;
 754                 af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 755                                                        addr4->sin_addr.s_addr);
 756                 if (af4_entry == NULL) {
 757                         ret_val = -ENOENT;
 758                         goto conn_setattr_return;
 759                 }
 760                 switch (af4_entry->type) {
 761                 case NETLBL_NLTYPE_CIPSOV4:
 762                         ret_val = cipso_v4_sock_setattr(sk,
 763                                                    af4_entry->type_def.cipsov4,
 764                                                    secattr);
 765                         break;
 766                 case NETLBL_NLTYPE_UNLABELED:
 767                         /* just delete the protocols we support for right now
 768                          * but we could remove other protocols if needed */
 769                         cipso_v4_sock_delattr(sk);
 770                         ret_val = 0;
 771                         break;
 772                 default:
 773                         ret_val = -ENOENT;
 774                 }
 775                 break;
 776 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 777         case AF_INET6:
 778                 /* since we don't support any IPv6 labeling protocols right
 779                  * now we can optimize everything away until we do */
 780                 ret_val = 0;
 781                 break;
 782 #endif /* IPv6 */
 783         default:
 784                 ret_val = -EPROTONOSUPPORT;
 785         }
 786
 787 conn_setattr_return:
 788         rcu_read_unlock();
 789         return ret_val;
 790 }
 791
 792 /**
 793  * netlbl_req_setattr - Label a request socket using the correct protocol
 794  * @req: the request socket to label
 795  * @secattr: the security attributes
 796  *
 797  * Description:
 798  * Attach the correct label to the given socket using the security attributes
 799  * specified in @secattr.  Returns zero on success, negative values on failure.
 800  *
 801  */
 802 int netlbl_req_setattr(struct request_sock *req,
 803                        const struct netlbl_lsm_secattr *secattr)
 804 {
 805         int ret_val;
 806         struct netlbl_dom_map *dom_entry;
 807         struct netlbl_domaddr4_map *af4_entry;
 808         u32 proto_type;
 809         struct cipso_v4_doi *proto_cv4;
 810
 811         rcu_read_lock();
 812         dom_entry = netlbl_domhsh_getentry(secattr->domain);
 813         if (dom_entry == NULL) {
 814                 ret_val = -ENOENT;
 815                 goto req_setattr_return;
 816         }
 817         switch (req->rsk_ops->family) {
 818         case AF_INET:
 819                 if (dom_entry->type == NETLBL_NLTYPE_ADDRSELECT) {
 820                         struct inet_request_sock *req_inet = inet_rsk(req);
 821                         af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 822                                                             req_inet->rmt_addr);
 823                         if (af4_entry == NULL) {
 824                                 ret_val = -ENOENT;
 825                                 goto req_setattr_return;
 826                         }
 827                         proto_type = af4_entry->type;
 828                         proto_cv4 = af4_entry->type_def.cipsov4;
 829                 } else {
 830                         proto_type = dom_entry->type;
 831                         proto_cv4 = dom_entry->type_def.cipsov4;
 832                 }
 833                 switch (proto_type) {
 834                 case NETLBL_NLTYPE_CIPSOV4:
 835                         ret_val = cipso_v4_req_setattr(req, proto_cv4, secattr);
 836                         break;
 837                 case NETLBL_NLTYPE_UNLABELED:
 838                         /* just delete the protocols we support for right now
 839                          * but we could remove other protocols if needed */
 840                         cipso_v4_req_delattr(req);
 841                         ret_val = 0;
 842                         break;
 843                 default:
 844                         ret_val = -ENOENT;
 845                 }
 846                 break;
 847 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 848         case AF_INET6:
 849                 /* since we don't support any IPv6 labeling protocols right
 850                  * now we can optimize everything away until we do */
 851                 ret_val = 0;
 852                 break;
 853 #endif /* IPv6 */
 854         default:
 855                 ret_val = -EPROTONOSUPPORT;
 856         }
 857
 858 req_setattr_return:
 859         rcu_read_unlock();
 860         return ret_val;
 861 }
 862
 863 /**
 864 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
 865 * @req: the socket
 866 *
 867 * Description:
 868 * Remove all the NetLabel labeling from @req.
 869 *
 870 */
 871 void netlbl_req_delattr(struct request_sock *req)
 872 {
 873         cipso_v4_req_delattr(req);
 874 }
 875
 876 /**
 877  * netlbl_skbuff_setattr - Label a packet using the correct protocol
 878  * @skb: the packet
 879  * @family: protocol family
 880  * @secattr: the security attributes
 881  *
 882  * Description:
 883  * Attach the correct label to the given packet using the security attributes
 884  * specified in @secattr.  Returns zero on success, negative values on failure.
 885  *
 886  */
 887 int netlbl_skbuff_setattr(struct sk_buff *skb,
 888                           u16 family,
 889                           const struct netlbl_lsm_secattr *secattr)
 890 {
 891         int ret_val;
 892         struct iphdr *hdr4;
 893         struct netlbl_domaddr4_map *af4_entry;
 894
 895         rcu_read_lock();
 896         switch (family) {
 897         case AF_INET:
 898                 hdr4 = ip_hdr(skb);
 899                 af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 900                                                        hdr4->daddr);
 901                 if (af4_entry == NULL) {
 902                         ret_val = -ENOENT;
 903                         goto skbuff_setattr_return;
 904                 }
 905                 switch (af4_entry->type) {
 906                 case NETLBL_NLTYPE_CIPSOV4:
 907                         ret_val = cipso_v4_skbuff_setattr(skb,
 908                                                    af4_entry->type_def.cipsov4,
 909                                                    secattr);
 910                         break;
 911                 case NETLBL_NLTYPE_UNLABELED:
 912                         /* just delete the protocols we support for right now
 913                          * but we could remove other protocols if needed */
 914                         ret_val = cipso_v4_skbuff_delattr(skb);
 915                         break;
 916                 default:
 917                         ret_val = -ENOENT;
 918                 }
 919                 break;
 920 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 921         case AF_INET6:
 922                 /* since we don't support any IPv6 labeling protocols right
 923                  * now we can optimize everything away until we do */
 924                 ret_val = 0;
 925                 break;
 926 #endif /* IPv6 */
 927         default:
 928                 ret_val = -EPROTONOSUPPORT;
 929         }
 930
 931 skbuff_setattr_return:
 932         rcu_read_unlock();
 933         return ret_val;
 934 }
 935
 936 /**
 937  * netlbl_skbuff_getattr - Determine the security attributes of a packet
 938  * @skb: the packet
 939  * @family: protocol family
 940  * @secattr: the security attributes
 941  *
 942  * Description:
 943  * Examines the given packet to see if a recognized form of packet labeling
 944  * is present, if so it parses the packet label and returns the security
 945  * attributes in @secattr.  Returns zero on success, negative values on
 946  * failure.
 947  *
 948  */
 949 int netlbl_skbuff_getattr(const struct sk_buff *skb,
 950                           u16 family,
 951                           struct netlbl_lsm_secattr *secattr)
 952 {
 953         switch (family) {
 954         case AF_INET:
 955                 if (CIPSO_V4_OPTEXIST(skb) &&
 956                     cipso_v4_skbuff_getattr(skb, secattr) == 0)
 957                         return 0;
 958                 break;
 959 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 960         case AF_INET6:
 961                 break;
 962 #endif /* IPv6 */
 963         }
 964
 965         return netlbl_unlabel_getattr(skb, family, secattr);
 966 }
 967
 968 /**
 969  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
 970  * @skb: the packet
 971  * @error: the error code
 972  * @gateway: true if host is acting as a gateway, false otherwise
 973  *
 974  * Description:
 975  * Deal with a LSM problem when handling the packet in @skb, typically this is
 976  * a permission denied problem (-EACCES).  The correct action is determined
 977  * according to the packet's labeling protocol.
 978  *
 979  */
 980 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
 981 {
 982         if (CIPSO_V4_OPTEXIST(skb))
 983                 cipso_v4_error(skb, error, gateway);
 984 }
 985
 986 /**
 987  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
 988  *
 989  * Description:
 990  * For all of the NetLabel protocols that support some form of label mapping
 991  * cache, invalidate the cache.  Returns zero on success, negative values on
 992  * error.
 993  *
 994  */
 995 void netlbl_cache_invalidate(void)
 996 {
 997         cipso_v4_cache_invalidate();
 998 }
 999
1000 /**
1001  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1002  * @skb: the packet
1003  * @secattr: the packet's security attributes
1004  *
1005  * Description:
1006  * Add the LSM security attributes for the given packet to the underlying
1007  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1008  * values on error.
1009  *
1010  */
1011 int netlbl_cache_add(const struct sk_buff *skb,
1012                      const struct netlbl_lsm_secattr *secattr)
1013 {
1014         if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1015                 return -ENOMSG;
1016
1017         if (CIPSO_V4_OPTEXIST(skb))
1018                 return cipso_v4_cache_add(skb, secattr);
1019
1020         return -ENOMSG;
1021 }
1022
1023 /*
1024  * Protocol Engine Functions
1025  */
1026
1027 /**
1028  * netlbl_audit_start - Start an audit message
1029  * @type: audit message type
1030  * @audit_info: NetLabel audit information
1031  *
1032  * Description:
1033  * Start an audit message using the type specified in @type and fill the audit
1034  * message with some fields common to all NetLabel audit messages.  This
1035  * function should only be used by protocol engines, not LSMs.  Returns a
1036  * pointer to the audit buffer on success, NULL on failure.
1037  *
1038  */
1039 struct audit_buffer *netlbl_audit_start(int type,
1040                                         struct netlbl_audit *audit_info)
1041 {
1042         return netlbl_audit_start_common(type, audit_info);
1043 }
1044
1045 /*
1046  * Setup Functions
1047  */
1048
1049 /**
1050  * netlbl_init - Initialize NetLabel
1051  *
1052  * Description:
1053  * Perform the required NetLabel initialization before first use.
1054  *
1055  */
1056 static int __init netlbl_init(void)
1057 {
1058         int ret_val;
1059
1060         printk(KERN_INFO "NetLabel: Initializing\n");
1061         printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1062                (1 << NETLBL_DOMHSH_BITSIZE));
1063         printk(KERN_INFO "NetLabel:  protocols ="
1064                " UNLABELED"
1065                " CIPSOv4"
1066                "\n");
1067
1068         ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1069         if (ret_val != 0)
1070                 goto init_failure;
1071
1072         ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1073         if (ret_val != 0)
1074                 goto init_failure;
1075
1076         ret_val = netlbl_netlink_init();
1077         if (ret_val != 0)
1078                 goto init_failure;
1079
1080         ret_val = netlbl_unlabel_defconf();
1081         if (ret_val != 0)
1082                 goto init_failure;
1083         printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1084
1085         return 0;
1086
1087 init_failure:
1088         panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1089 }
1090
1091 subsys_initcall(netlbl_init);