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@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/init.h>
  32 #include <linux/types.h>
  33 #include <linux/slab.h>
  34 #include <linux/audit.h>
  35 #include <linux/in.h>
  36 #include <linux/in6.h>
  37 #include <net/ip.h>
  38 #include <net/ipv6.h>
  39 #include <net/netlabel.h>
  40 #include <net/cipso_ipv4.h>
  41 #include <asm/bug.h>
  42 #include <linux/atomic.h>
  43
  44 #include "netlabel_domainhash.h"
  45 #include "netlabel_unlabeled.h"
  46 #include "netlabel_cipso_v4.h"
  47 #include "netlabel_user.h"
  48 #include "netlabel_mgmt.h"
  49 #include "netlabel_addrlist.h"
  50
  51 /*
  52  * Configuration Functions
  53  */
  54
  55 /**
  56  * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping
  57  * @domain: the domain mapping to remove
  58  * @family: address family
  59  * @addr: IP address
  60  * @mask: IP address mask
  61  * @audit_info: NetLabel audit information
  62  *
  63  * Description:
  64  * Removes a NetLabel/LSM domain mapping.  A @domain value of NULL causes the
  65  * default domain mapping to be removed.  Returns zero on success, negative
  66  * values on failure.
  67  *
  68  */
  69 int netlbl_cfg_map_del(const char *domain,
  70                        u16 family,
  71                        const void *addr,
  72                        const void *mask,
  73                        struct netlbl_audit *audit_info)
  74 {
  75         if (addr == NULL && mask == NULL) {
  76                 return netlbl_domhsh_remove(domain, audit_info);
  77         } else if (addr != NULL && mask != NULL) {
  78                 switch (family) {
  79                 case AF_INET:
  80                         return netlbl_domhsh_remove_af4(domain, addr, mask,
  81                                                         audit_info);
  82                 default:
  83                         return -EPFNOSUPPORT;
  84                 }
  85         } else
  86                 return -EINVAL;
  87 }
  88
  89 /**
  90  * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping
  91  * @domain: the domain mapping to add
  92  * @family: address family
  93  * @addr: IP address
  94  * @mask: IP address mask
  95  * @audit_info: NetLabel audit information
  96  *
  97  * Description:
  98  * Adds a new unlabeled NetLabel/LSM domain mapping.  A @domain value of NULL
  99  * causes a new default domain mapping to be added.  Returns zero on success,
 100  * negative values on failure.
 101  *
 102  */
 103 int netlbl_cfg_unlbl_map_add(const char *domain,
 104                              u16 family,
 105                              const void *addr,
 106                              const void *mask,
 107                              struct netlbl_audit *audit_info)
 108 {
 109         int ret_val = -ENOMEM;
 110         struct netlbl_dom_map *entry;
 111         struct netlbl_domaddr_map *addrmap = NULL;
 112         struct netlbl_domaddr4_map *map4 = NULL;
 113         struct netlbl_domaddr6_map *map6 = NULL;
 114         const struct in_addr *addr4, *mask4;
 115         const struct in6_addr *addr6, *mask6;
 116
 117         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 118         if (entry == NULL)
 119                 return -ENOMEM;
 120         if (domain != NULL) {
 121                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 122                 if (entry->domain == NULL)
 123                         goto cfg_unlbl_map_add_failure;
 124         }
 125
 126         if (addr == NULL && mask == NULL)
 127                 entry->type = NETLBL_NLTYPE_UNLABELED;
 128         else if (addr != NULL && mask != NULL) {
 129                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 130                 if (addrmap == NULL)
 131                         goto cfg_unlbl_map_add_failure;
 132                 INIT_LIST_HEAD(&addrmap->list4);
 133                 INIT_LIST_HEAD(&addrmap->list6);
 134
 135                 switch (family) {
 136                 case AF_INET:
 137                         addr4 = addr;
 138                         mask4 = mask;
 139                         map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
 140                         if (map4 == NULL)
 141                                 goto cfg_unlbl_map_add_failure;
 142                         map4->type = NETLBL_NLTYPE_UNLABELED;
 143                         map4->list.addr = addr4->s_addr & mask4->s_addr;
 144                         map4->list.mask = mask4->s_addr;
 145                         map4->list.valid = 1;
 146                         ret_val = netlbl_af4list_add(&map4->list,
 147                                                      &addrmap->list4);
 148                         if (ret_val != 0)
 149                                 goto cfg_unlbl_map_add_failure;
 150                         break;
 151                 case AF_INET6:
 152                         addr6 = addr;
 153                         mask6 = mask;
 154                         map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
 155                         if (map6 == NULL)
 156                                 goto cfg_unlbl_map_add_failure;
 157                         map6->type = NETLBL_NLTYPE_UNLABELED;
 158                         map6->list.addr = *addr6;
 159                         map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
 160                         map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
 161                         map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
 162                         map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
 163                         map6->list.mask = *mask6;
 164                         map6->list.valid = 1;
 165                         ret_val = netlbl_af4list_add(&map4->list,
 166                                                      &addrmap->list4);
 167                         if (ret_val != 0)
 168                                 goto cfg_unlbl_map_add_failure;
 169                         break;
 170                 default:
 171                         goto cfg_unlbl_map_add_failure;
 172                         break;
 173                 }
 174
 175                 entry->type_def.addrsel = addrmap;
 176                 entry->type = NETLBL_NLTYPE_ADDRSELECT;
 177         } else {
 178                 ret_val = -EINVAL;
 179                 goto cfg_unlbl_map_add_failure;
 180         }
 181
 182         ret_val = netlbl_domhsh_add(entry, audit_info);
 183         if (ret_val != 0)
 184                 goto cfg_unlbl_map_add_failure;
 185
 186         return 0;
 187
 188 cfg_unlbl_map_add_failure:
 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                 goto out_entry;
 345         if (domain != NULL) {
 346                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 347                 if (entry->domain == NULL)
 348                         goto out_domain;
 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 out_addrmap;
 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 out_addrinfo;
 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 out_addrmap;
 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         kfree(addrinfo);
 388 out_addrinfo:
 389         kfree(addrmap);
 390 out_addrmap:
 391         kfree(entry->domain);
 392 out_domain:
 393         kfree(entry);
 394 out_entry:
 395         cipso_v4_doi_putdef(doi_def);
 396         return ret_val;
 397 }
 398
 399 /*
 400  * Security Attribute Functions
 401  */
 402
 403 /**
 404  * netlbl_secattr_catmap_walk - Walk a LSM secattr catmap looking for a bit
 405  * @catmap: the category bitmap
 406  * @offset: the offset to start searching at, in bits
 407  *
 408  * Description:
 409  * This function walks a LSM secattr category bitmap starting at @offset and
 410  * returns the spot of the first set bit or -ENOENT if no bits are set.
 411  *
 412  */
 413 int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
 414                                u32 offset)
 415 {
 416         struct netlbl_lsm_secattr_catmap *iter = catmap;
 417         u32 node_idx;
 418         u32 node_bit;
 419         NETLBL_CATMAP_MAPTYPE bitmap;
 420
 421         if (offset > iter->startbit) {
 422                 while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 423                         iter = iter->next;
 424                         if (iter == NULL)
 425                                 return -ENOENT;
 426                 }
 427                 node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 428                 node_bit = offset - iter->startbit -
 429                            (NETLBL_CATMAP_MAPSIZE * node_idx);
 430         } else {
 431                 node_idx = 0;
 432                 node_bit = 0;
 433         }
 434         bitmap = iter->bitmap[node_idx] >> node_bit;
 435
 436         for (;;) {
 437                 if (bitmap != 0) {
 438                         while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
 439                                 bitmap >>= 1;
 440                                 node_bit++;
 441                         }
 442                         return iter->startbit +
 443                                 (NETLBL_CATMAP_MAPSIZE * node_idx) + node_bit;
 444                 }
 445                 if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
 446                         if (iter->next != NULL) {
 447                                 iter = iter->next;
 448                                 node_idx = 0;
 449                         } else
 450                                 return -ENOENT;
 451                 }
 452                 bitmap = iter->bitmap[node_idx];
 453                 node_bit = 0;
 454         }
 455
 456         return -ENOENT;
 457 }
 458
 459 /**
 460  * netlbl_secattr_catmap_walk_rng - Find the end of a string of set bits
 461  * @catmap: the category bitmap
 462  * @offset: the offset to start searching at, in bits
 463  *
 464  * Description:
 465  * This function walks a LSM secattr category bitmap starting at @offset and
 466  * returns the spot of the first cleared bit or -ENOENT if the offset is past
 467  * the end of the bitmap.
 468  *
 469  */
 470 int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
 471                                    u32 offset)
 472 {
 473         struct netlbl_lsm_secattr_catmap *iter = catmap;
 474         u32 node_idx;
 475         u32 node_bit;
 476         NETLBL_CATMAP_MAPTYPE bitmask;
 477         NETLBL_CATMAP_MAPTYPE bitmap;
 478
 479         if (offset > iter->startbit) {
 480                 while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 481                         iter = iter->next;
 482                         if (iter == NULL)
 483                                 return -ENOENT;
 484                 }
 485                 node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 486                 node_bit = offset - iter->startbit -
 487                            (NETLBL_CATMAP_MAPSIZE * node_idx);
 488         } else {
 489                 node_idx = 0;
 490                 node_bit = 0;
 491         }
 492         bitmask = NETLBL_CATMAP_BIT << node_bit;
 493
 494         for (;;) {
 495                 bitmap = iter->bitmap[node_idx];
 496                 while (bitmask != 0 && (bitmap & bitmask) != 0) {
 497                         bitmask <<= 1;
 498                         node_bit++;
 499                 }
 500
 501                 if (bitmask != 0)
 502                         return iter->startbit +
 503                                 (NETLBL_CATMAP_MAPSIZE * node_idx) +
 504                                 node_bit - 1;
 505                 else if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
 506                         if (iter->next == NULL)
 507                                 return iter->startbit + NETLBL_CATMAP_SIZE - 1;
 508                         iter = iter->next;
 509                         node_idx = 0;
 510                 }
 511                 bitmask = NETLBL_CATMAP_BIT;
 512                 node_bit = 0;
 513         }
 514
 515         return -ENOENT;
 516 }
 517
 518 /**
 519  * netlbl_secattr_catmap_setbit - Set a bit in a LSM secattr catmap
 520  * @catmap: the category bitmap
 521  * @bit: the bit to set
 522  * @flags: memory allocation flags
 523  *
 524  * Description:
 525  * Set the bit specified by @bit in @catmap.  Returns zero on success,
 526  * negative values on failure.
 527  *
 528  */
 529 int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
 530                                  u32 bit,
 531                                  gfp_t flags)
 532 {
 533         struct netlbl_lsm_secattr_catmap *iter = catmap;
 534         u32 node_bit;
 535         u32 node_idx;
 536
 537         while (iter->next != NULL &&
 538                bit >= (iter->startbit + NETLBL_CATMAP_SIZE))
 539                 iter = iter->next;
 540         if (bit >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 541                 iter->next = netlbl_secattr_catmap_alloc(flags);
 542                 if (iter->next == NULL)
 543                         return -ENOMEM;
 544                 iter = iter->next;
 545                 iter->startbit = bit & ~(NETLBL_CATMAP_SIZE - 1);
 546         }
 547
 548         /* gcc always rounds to zero when doing integer division */
 549         node_idx = (bit - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
 550         node_bit = bit - iter->startbit - (NETLBL_CATMAP_MAPSIZE * node_idx);
 551         iter->bitmap[node_idx] |= NETLBL_CATMAP_BIT << node_bit;
 552
 553         return 0;
 554 }
 555
 556 /**
 557  * netlbl_secattr_catmap_setrng - Set a range of bits in a LSM secattr catmap
 558  * @catmap: the category bitmap
 559  * @start: the starting bit
 560  * @end: the last bit in the string
 561  * @flags: memory allocation flags
 562  *
 563  * Description:
 564  * Set a range of bits, starting at @start and ending with @end.  Returns zero
 565  * on success, negative values on failure.
 566  *
 567  */
 568 int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
 569                                  u32 start,
 570                                  u32 end,
 571                                  gfp_t flags)
 572 {
 573         int ret_val = 0;
 574         struct netlbl_lsm_secattr_catmap *iter = catmap;
 575         u32 iter_max_spot;
 576         u32 spot;
 577
 578         /* XXX - This could probably be made a bit faster by combining writes
 579          * to the catmap instead of setting a single bit each time, but for
 580          * right now skipping to the start of the range in the catmap should
 581          * be a nice improvement over calling the individual setbit function
 582          * repeatedly from a loop. */
 583
 584         while (iter->next != NULL &&
 585                start >= (iter->startbit + NETLBL_CATMAP_SIZE))
 586                 iter = iter->next;
 587         iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
 588
 589         for (spot = start; spot <= end && ret_val == 0; spot++) {
 590                 if (spot >= iter_max_spot && iter->next != NULL) {
 591                         iter = iter->next;
 592                         iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
 593                 }
 594                 ret_val = netlbl_secattr_catmap_setbit(iter, spot, GFP_ATOMIC);
 595         }
 596
 597         return ret_val;
 598 }
 599
 600 /*
 601  * LSM Functions
 602  */
 603
 604 /**
 605  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
 606  *
 607  * Description:
 608  * The LSM can use this function to determine if it should use NetLabel
 609  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
 610  * considered to be enabled when it's configuration contains a valid setup for
 611  * at least one labeled protocol (i.e. NetLabel can understand incoming
 612  * labeled packets of at least one type); otherwise NetLabel is considered to
 613  * be disabled.
 614  *
 615  */
 616 int netlbl_enabled(void)
 617 {
 618         /* At some point we probably want to expose this mechanism to the user
 619          * as well so that admins can toggle NetLabel regardless of the
 620          * configuration */
 621         return (atomic_read(&netlabel_mgmt_protocount) > 0);
 622 }
 623
 624 /**
 625  * netlbl_sock_setattr - Label a socket using the correct protocol
 626  * @sk: the socket to label
 627  * @family: protocol family
 628  * @secattr: the security attributes
 629  *
 630  * Description:
 631  * Attach the correct label to the given socket using the security attributes
 632  * specified in @secattr.  This function requires exclusive access to @sk,
 633  * which means it either needs to be in the process of being created or locked.
 634  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
 635  * network address selectors (can't blindly label the socket), and negative
 636  * values on all other failures.
 637  *
 638  */
 639 int netlbl_sock_setattr(struct sock *sk,
 640                         u16 family,
 641                         const struct netlbl_lsm_secattr *secattr)
 642 {
 643         int ret_val;
 644         struct netlbl_dom_map *dom_entry;
 645
 646         rcu_read_lock();
 647         dom_entry = netlbl_domhsh_getentry(secattr->domain);
 648         if (dom_entry == NULL) {
 649                 ret_val = -ENOENT;
 650                 goto socket_setattr_return;
 651         }
 652         switch (family) {
 653         case AF_INET:
 654                 switch (dom_entry->type) {
 655                 case NETLBL_NLTYPE_ADDRSELECT:
 656                         ret_val = -EDESTADDRREQ;
 657                         break;
 658                 case NETLBL_NLTYPE_CIPSOV4:
 659                         ret_val = cipso_v4_sock_setattr(sk,
 660                                                     dom_entry->type_def.cipsov4,
 661                                                     secattr);
 662                         break;
 663                 case NETLBL_NLTYPE_UNLABELED:
 664                         ret_val = 0;
 665                         break;
 666                 default:
 667                         ret_val = -ENOENT;
 668                 }
 669                 break;
 670 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 671         case AF_INET6:
 672                 /* since we don't support any IPv6 labeling protocols right
 673                  * now we can optimize everything away until we do */
 674                 ret_val = 0;
 675                 break;
 676 #endif /* IPv6 */
 677         default:
 678                 ret_val = -EPROTONOSUPPORT;
 679         }
 680
 681 socket_setattr_return:
 682         rcu_read_unlock();
 683         return ret_val;
 684 }
 685
 686 /**
 687  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
 688  * @sk: the socket
 689  *
 690  * Description:
 691  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
 692  * ensuring that @sk is locked.
 693  *
 694  */
 695 void netlbl_sock_delattr(struct sock *sk)
 696 {
 697         cipso_v4_sock_delattr(sk);
 698 }
 699
 700 /**
 701  * netlbl_sock_getattr - Determine the security attributes of a sock
 702  * @sk: the sock
 703  * @secattr: the security attributes
 704  *
 705  * Description:
 706  * Examines the given sock to see if any NetLabel style labeling has been
 707  * applied to the sock, if so it parses the socket label and returns the
 708  * security attributes in @secattr.  Returns zero on success, negative values
 709  * on failure.
 710  *
 711  */
 712 int netlbl_sock_getattr(struct sock *sk,
 713                         struct netlbl_lsm_secattr *secattr)
 714 {
 715         int ret_val;
 716
 717         switch (sk->sk_family) {
 718         case AF_INET:
 719                 ret_val = cipso_v4_sock_getattr(sk, secattr);
 720                 break;
 721 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 722         case AF_INET6:
 723                 ret_val = -ENOMSG;
 724                 break;
 725 #endif /* IPv6 */
 726         default:
 727                 ret_val = -EPROTONOSUPPORT;
 728         }
 729
 730         return ret_val;
 731 }
 732
 733 /**
 734  * netlbl_conn_setattr - Label a connected socket using the correct protocol
 735  * @sk: the socket to label
 736  * @addr: the destination address
 737  * @secattr: the security attributes
 738  *
 739  * Description:
 740  * Attach the correct label to the given connected socket using the security
 741  * attributes specified in @secattr.  The caller is responsible for ensuring
 742  * that @sk is locked.  Returns zero on success, negative values on failure.
 743  *
 744  */
 745 int netlbl_conn_setattr(struct sock *sk,
 746                         struct sockaddr *addr,
 747                         const struct netlbl_lsm_secattr *secattr)
 748 {
 749         int ret_val;
 750         struct sockaddr_in *addr4;
 751         struct netlbl_domaddr4_map *af4_entry;
 752
 753         rcu_read_lock();
 754         switch (addr->sa_family) {
 755         case AF_INET:
 756                 addr4 = (struct sockaddr_in *)addr;
 757                 af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 758                                                        addr4->sin_addr.s_addr);
 759                 if (af4_entry == NULL) {
 760                         ret_val = -ENOENT;
 761                         goto conn_setattr_return;
 762                 }
 763                 switch (af4_entry->type) {
 764                 case NETLBL_NLTYPE_CIPSOV4:
 765                         ret_val = cipso_v4_sock_setattr(sk,
 766                                                    af4_entry->type_def.cipsov4,
 767                                                    secattr);
 768                         break;
 769                 case NETLBL_NLTYPE_UNLABELED:
 770                         /* just delete the protocols we support for right now
 771                          * but we could remove other protocols if needed */
 772                         cipso_v4_sock_delattr(sk);
 773                         ret_val = 0;
 774                         break;
 775                 default:
 776                         ret_val = -ENOENT;
 777                 }
 778                 break;
 779 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 780         case AF_INET6:
 781                 /* since we don't support any IPv6 labeling protocols right
 782                  * now we can optimize everything away until we do */
 783                 ret_val = 0;
 784                 break;
 785 #endif /* IPv6 */
 786         default:
 787                 ret_val = -EPROTONOSUPPORT;
 788         }
 789
 790 conn_setattr_return:
 791         rcu_read_unlock();
 792         return ret_val;
 793 }
 794
 795 /**
 796  * netlbl_req_setattr - Label a request socket using the correct protocol
 797  * @req: the request socket to label
 798  * @secattr: the security attributes
 799  *
 800  * Description:
 801  * Attach the correct label to the given socket using the security attributes
 802  * specified in @secattr.  Returns zero on success, negative values on failure.
 803  *
 804  */
 805 int netlbl_req_setattr(struct request_sock *req,
 806                        const struct netlbl_lsm_secattr *secattr)
 807 {
 808         int ret_val;
 809         struct netlbl_dom_map *dom_entry;
 810         struct netlbl_domaddr4_map *af4_entry;
 811         u32 proto_type;
 812         struct cipso_v4_doi *proto_cv4;
 813
 814         rcu_read_lock();
 815         dom_entry = netlbl_domhsh_getentry(secattr->domain);
 816         if (dom_entry == NULL) {
 817                 ret_val = -ENOENT;
 818                 goto req_setattr_return;
 819         }
 820         switch (req->rsk_ops->family) {
 821         case AF_INET:
 822                 if (dom_entry->type == NETLBL_NLTYPE_ADDRSELECT) {
 823                         struct inet_request_sock *req_inet = inet_rsk(req);
 824                         af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 825                                                             req_inet->rmt_addr);
 826                         if (af4_entry == NULL) {
 827                                 ret_val = -ENOENT;
 828                                 goto req_setattr_return;
 829                         }
 830                         proto_type = af4_entry->type;
 831                         proto_cv4 = af4_entry->type_def.cipsov4;
 832                 } else {
 833                         proto_type = dom_entry->type;
 834                         proto_cv4 = dom_entry->type_def.cipsov4;
 835                 }
 836                 switch (proto_type) {
 837                 case NETLBL_NLTYPE_CIPSOV4:
 838                         ret_val = cipso_v4_req_setattr(req, proto_cv4, secattr);
 839                         break;
 840                 case NETLBL_NLTYPE_UNLABELED:
 841                         /* just delete the protocols we support for right now
 842                          * but we could remove other protocols if needed */
 843                         cipso_v4_req_delattr(req);
 844                         ret_val = 0;
 845                         break;
 846                 default:
 847                         ret_val = -ENOENT;
 848                 }
 849                 break;
 850 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 851         case AF_INET6:
 852                 /* since we don't support any IPv6 labeling protocols right
 853                  * now we can optimize everything away until we do */
 854                 ret_val = 0;
 855                 break;
 856 #endif /* IPv6 */
 857         default:
 858                 ret_val = -EPROTONOSUPPORT;
 859         }
 860
 861 req_setattr_return:
 862         rcu_read_unlock();
 863         return ret_val;
 864 }
 865
 866 /**
 867 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
 868 * @req: the socket
 869 *
 870 * Description:
 871 * Remove all the NetLabel labeling from @req.
 872 *
 873 */
 874 void netlbl_req_delattr(struct request_sock *req)
 875 {
 876         cipso_v4_req_delattr(req);
 877 }
 878
 879 /**
 880  * netlbl_skbuff_setattr - Label a packet using the correct protocol
 881  * @skb: the packet
 882  * @family: protocol family
 883  * @secattr: the security attributes
 884  *
 885  * Description:
 886  * Attach the correct label to the given packet using the security attributes
 887  * specified in @secattr.  Returns zero on success, negative values on failure.
 888  *
 889  */
 890 int netlbl_skbuff_setattr(struct sk_buff *skb,
 891                           u16 family,
 892                           const struct netlbl_lsm_secattr *secattr)
 893 {
 894         int ret_val;
 895         struct iphdr *hdr4;
 896         struct netlbl_domaddr4_map *af4_entry;
 897
 898         rcu_read_lock();
 899         switch (family) {
 900         case AF_INET:
 901                 hdr4 = ip_hdr(skb);
 902                 af4_entry = netlbl_domhsh_getentry_af4(secattr->domain,
 903                                                        hdr4->daddr);
 904                 if (af4_entry == NULL) {
 905                         ret_val = -ENOENT;
 906                         goto skbuff_setattr_return;
 907                 }
 908                 switch (af4_entry->type) {
 909                 case NETLBL_NLTYPE_CIPSOV4:
 910                         ret_val = cipso_v4_skbuff_setattr(skb,
 911                                                    af4_entry->type_def.cipsov4,
 912                                                    secattr);
 913                         break;
 914                 case NETLBL_NLTYPE_UNLABELED:
 915                         /* just delete the protocols we support for right now
 916                          * but we could remove other protocols if needed */
 917                         ret_val = cipso_v4_skbuff_delattr(skb);
 918                         break;
 919                 default:
 920                         ret_val = -ENOENT;
 921                 }
 922                 break;
 923 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 924         case AF_INET6:
 925                 /* since we don't support any IPv6 labeling protocols right
 926                  * now we can optimize everything away until we do */
 927                 ret_val = 0;
 928                 break;
 929 #endif /* IPv6 */
 930         default:
 931                 ret_val = -EPROTONOSUPPORT;
 932         }
 933
 934 skbuff_setattr_return:
 935         rcu_read_unlock();
 936         return ret_val;
 937 }
 938
 939 /**
 940  * netlbl_skbuff_getattr - Determine the security attributes of a packet
 941  * @skb: the packet
 942  * @family: protocol family
 943  * @secattr: the security attributes
 944  *
 945  * Description:
 946  * Examines the given packet to see if a recognized form of packet labeling
 947  * is present, if so it parses the packet label and returns the security
 948  * attributes in @secattr.  Returns zero on success, negative values on
 949  * failure.
 950  *
 951  */
 952 int netlbl_skbuff_getattr(const struct sk_buff *skb,
 953                           u16 family,
 954                           struct netlbl_lsm_secattr *secattr)
 955 {
 956         switch (family) {
 957         case AF_INET:
 958                 if (CIPSO_V4_OPTEXIST(skb) &&
 959                     cipso_v4_skbuff_getattr(skb, secattr) == 0)
 960                         return 0;
 961                 break;
 962 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 963         case AF_INET6:
 964                 break;
 965 #endif /* IPv6 */
 966         }
 967
 968         return netlbl_unlabel_getattr(skb, family, secattr);
 969 }
 970
 971 /**
 972  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
 973  * @skb: the packet
 974  * @error: the error code
 975  * @gateway: true if host is acting as a gateway, false otherwise
 976  *
 977  * Description:
 978  * Deal with a LSM problem when handling the packet in @skb, typically this is
 979  * a permission denied problem (-EACCES).  The correct action is determined
 980  * according to the packet's labeling protocol.
 981  *
 982  */
 983 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
 984 {
 985         if (CIPSO_V4_OPTEXIST(skb))
 986                 cipso_v4_error(skb, error, gateway);
 987 }
 988
 989 /**
 990  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
 991  *
 992  * Description:
 993  * For all of the NetLabel protocols that support some form of label mapping
 994  * cache, invalidate the cache.  Returns zero on success, negative values on
 995  * error.
 996  *
 997  */
 998 void netlbl_cache_invalidate(void)
 999 {
1000         cipso_v4_cache_invalidate();
1001 }
1002
1003 /**
1004  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1005  * @skb: the packet
1006  * @secattr: the packet's security attributes
1007  *
1008  * Description:
1009  * Add the LSM security attributes for the given packet to the underlying
1010  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1011  * values on error.
1012  *
1013  */
1014 int netlbl_cache_add(const struct sk_buff *skb,
1015                      const struct netlbl_lsm_secattr *secattr)
1016 {
1017         if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1018                 return -ENOMSG;
1019
1020         if (CIPSO_V4_OPTEXIST(skb))
1021                 return cipso_v4_cache_add(skb, secattr);
1022
1023         return -ENOMSG;
1024 }
1025
1026 /*
1027  * Protocol Engine Functions
1028  */
1029
1030 /**
1031  * netlbl_audit_start - Start an audit message
1032  * @type: audit message type
1033  * @audit_info: NetLabel audit information
1034  *
1035  * Description:
1036  * Start an audit message using the type specified in @type and fill the audit
1037  * message with some fields common to all NetLabel audit messages.  This
1038  * function should only be used by protocol engines, not LSMs.  Returns a
1039  * pointer to the audit buffer on success, NULL on failure.
1040  *
1041  */
1042 struct audit_buffer *netlbl_audit_start(int type,
1043                                         struct netlbl_audit *audit_info)
1044 {
1045         return netlbl_audit_start_common(type, audit_info);
1046 }
1047
1048 /*
1049  * Setup Functions
1050  */
1051
1052 /**
1053  * netlbl_init - Initialize NetLabel
1054  *
1055  * Description:
1056  * Perform the required NetLabel initialization before first use.
1057  *
1058  */
1059 static int __init netlbl_init(void)
1060 {
1061         int ret_val;
1062
1063         printk(KERN_INFO "NetLabel: Initializing\n");
1064         printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1065                (1 << NETLBL_DOMHSH_BITSIZE));
1066         printk(KERN_INFO "NetLabel:  protocols ="
1067                " UNLABELED"
1068                " CIPSOv4"
1069                "\n");
1070
1071         ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1072         if (ret_val != 0)
1073                 goto init_failure;
1074
1075         ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1076         if (ret_val != 0)
1077                 goto init_failure;
1078
1079         ret_val = netlbl_netlink_init();
1080         if (ret_val != 0)
1081                 goto init_failure;
1082
1083         ret_val = netlbl_unlabel_defconf();
1084         if (ret_val != 0)
1085                 goto init_failure;
1086         printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1087
1088         return 0;
1089
1090 init_failure:
1091         panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1092 }
1093
1094 subsys_initcall(netlbl_init);