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, see <http://www.gnu.org/licenses/>.
  27  *
  28  */
  29
  30 #include <linux/init.h>
  31 #include <linux/types.h>
  32 #include <linux/slab.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 <linux/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
 114         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 115         if (entry == NULL)
 116                 return -ENOMEM;
 117         if (domain != NULL) {
 118                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 119                 if (entry->domain == NULL)
 120                         goto cfg_unlbl_map_add_failure;
 121         }
 122
 123         if (addr == NULL && mask == NULL)
 124                 entry->def.type = NETLBL_NLTYPE_UNLABELED;
 125         else if (addr != NULL && mask != NULL) {
 126                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 127                 if (addrmap == NULL)
 128                         goto cfg_unlbl_map_add_failure;
 129                 INIT_LIST_HEAD(&addrmap->list4);
 130                 INIT_LIST_HEAD(&addrmap->list6);
 131
 132                 switch (family) {
 133                 case AF_INET: {
 134                         const struct in_addr *addr4 = addr;
 135                         const struct in_addr *mask4 = mask;
 136                         map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
 137                         if (map4 == NULL)
 138                                 goto cfg_unlbl_map_add_failure;
 139                         map4->def.type = NETLBL_NLTYPE_UNLABELED;
 140                         map4->list.addr = addr4->s_addr & mask4->s_addr;
 141                         map4->list.mask = mask4->s_addr;
 142                         map4->list.valid = 1;
 143                         ret_val = netlbl_af4list_add(&map4->list,
 144                                                      &addrmap->list4);
 145                         if (ret_val != 0)
 146                                 goto cfg_unlbl_map_add_failure;
 147                         break;
 148                         }
 149 #if IS_ENABLED(CONFIG_IPV6)
 150                 case AF_INET6: {
 151                         const struct in6_addr *addr6 = addr;
 152                         const struct in6_addr *mask6 = mask;
 153                         map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
 154                         if (map6 == NULL)
 155                                 goto cfg_unlbl_map_add_failure;
 156                         map6->def.type = NETLBL_NLTYPE_UNLABELED;
 157                         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                         map6->list.mask = *mask6;
 163                         map6->list.valid = 1;
 164                         ret_val = netlbl_af6list_add(&map6->list,
 165                                                      &addrmap->list6);
 166                         if (ret_val != 0)
 167                                 goto cfg_unlbl_map_add_failure;
 168                         break;
 169                         }
 170 #endif /* IPv6 */
 171                 default:
 172                         goto cfg_unlbl_map_add_failure;
 173                         break;
 174                 }
 175
 176                 entry->def.addrsel = addrmap;
 177                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 178         } else {
 179                 ret_val = -EINVAL;
 180                 goto cfg_unlbl_map_add_failure;
 181         }
 182
 183         ret_val = netlbl_domhsh_add(entry, audit_info);
 184         if (ret_val != 0)
 185                 goto cfg_unlbl_map_add_failure;
 186
 187         return 0;
 188
 189 cfg_unlbl_map_add_failure:
 190         kfree(entry->domain);
 191         kfree(entry);
 192         kfree(addrmap);
 193         kfree(map4);
 194         kfree(map6);
 195         return ret_val;
 196 }
 197
 198
 199 /**
 200  * netlbl_cfg_unlbl_static_add - Adds a new static label
 201  * @net: network namespace
 202  * @dev_name: interface name
 203  * @addr: IP address in network byte order (struct in[6]_addr)
 204  * @mask: address mask in network byte order (struct in[6]_addr)
 205  * @family: address family
 206  * @secid: LSM secid value for the entry
 207  * @audit_info: NetLabel audit information
 208  *
 209  * Description:
 210  * Adds a new NetLabel static label to be used when protocol provided labels
 211  * are not present on incoming traffic.  If @dev_name is NULL then the default
 212  * interface will be used.  Returns zero on success, negative values on failure.
 213  *
 214  */
 215 int netlbl_cfg_unlbl_static_add(struct net *net,
 216                                 const char *dev_name,
 217                                 const void *addr,
 218                                 const void *mask,
 219                                 u16 family,
 220                                 u32 secid,
 221                                 struct netlbl_audit *audit_info)
 222 {
 223         u32 addr_len;
 224
 225         switch (family) {
 226         case AF_INET:
 227                 addr_len = sizeof(struct in_addr);
 228                 break;
 229 #if IS_ENABLED(CONFIG_IPV6)
 230         case AF_INET6:
 231                 addr_len = sizeof(struct in6_addr);
 232                 break;
 233 #endif /* IPv6 */
 234         default:
 235                 return -EPFNOSUPPORT;
 236         }
 237
 238         return netlbl_unlhsh_add(net,
 239                                  dev_name, addr, mask, addr_len,
 240                                  secid, audit_info);
 241 }
 242
 243 /**
 244  * netlbl_cfg_unlbl_static_del - Removes an existing static label
 245  * @net: network namespace
 246  * @dev_name: interface name
 247  * @addr: IP address in network byte order (struct in[6]_addr)
 248  * @mask: address mask in network byte order (struct in[6]_addr)
 249  * @family: address family
 250  * @secid: LSM secid value for the entry
 251  * @audit_info: NetLabel audit information
 252  *
 253  * Description:
 254  * Removes an existing NetLabel static label used when protocol provided labels
 255  * are not present on incoming traffic.  If @dev_name is NULL then the default
 256  * interface will be used.  Returns zero on success, negative values on failure.
 257  *
 258  */
 259 int netlbl_cfg_unlbl_static_del(struct net *net,
 260                                 const char *dev_name,
 261                                 const void *addr,
 262                                 const void *mask,
 263                                 u16 family,
 264                                 struct netlbl_audit *audit_info)
 265 {
 266         u32 addr_len;
 267
 268         switch (family) {
 269         case AF_INET:
 270                 addr_len = sizeof(struct in_addr);
 271                 break;
 272 #if IS_ENABLED(CONFIG_IPV6)
 273         case AF_INET6:
 274                 addr_len = sizeof(struct in6_addr);
 275                 break;
 276 #endif /* IPv6 */
 277         default:
 278                 return -EPFNOSUPPORT;
 279         }
 280
 281         return netlbl_unlhsh_remove(net,
 282                                     dev_name, addr, mask, addr_len,
 283                                     audit_info);
 284 }
 285
 286 /**
 287  * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition
 288  * @doi_def: CIPSO DOI definition
 289  * @audit_info: NetLabel audit information
 290  *
 291  * Description:
 292  * Add a new CIPSO DOI definition as defined by @doi_def.  Returns zero on
 293  * success and negative values on failure.
 294  *
 295  */
 296 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
 297                            struct netlbl_audit *audit_info)
 298 {
 299         return cipso_v4_doi_add(doi_def, audit_info);
 300 }
 301
 302 /**
 303  * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition
 304  * @doi: CIPSO DOI
 305  * @audit_info: NetLabel audit information
 306  *
 307  * Description:
 308  * Remove an existing CIPSO DOI definition matching @doi.  Returns zero on
 309  * success and negative values on failure.
 310  *
 311  */
 312 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info)
 313 {
 314         cipso_v4_doi_remove(doi, audit_info);
 315 }
 316
 317 /**
 318  * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping
 319  * @doi: the CIPSO DOI
 320  * @domain: the domain mapping to add
 321  * @addr: IP address
 322  * @mask: IP address mask
 323  * @audit_info: NetLabel audit information
 324  *
 325  * Description:
 326  * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel
 327  * subsystem.  A @domain value of NULL adds a new default domain mapping.
 328  * Returns zero on success, negative values on failure.
 329  *
 330  */
 331 int netlbl_cfg_cipsov4_map_add(u32 doi,
 332                                const char *domain,
 333                                const struct in_addr *addr,
 334                                const struct in_addr *mask,
 335                                struct netlbl_audit *audit_info)
 336 {
 337         int ret_val = -ENOMEM;
 338         struct cipso_v4_doi *doi_def;
 339         struct netlbl_dom_map *entry;
 340         struct netlbl_domaddr_map *addrmap = NULL;
 341         struct netlbl_domaddr4_map *addrinfo = NULL;
 342
 343         doi_def = cipso_v4_doi_getdef(doi);
 344         if (doi_def == NULL)
 345                 return -ENOENT;
 346
 347         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 348         if (entry == NULL)
 349                 goto out_entry;
 350         if (domain != NULL) {
 351                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 352                 if (entry->domain == NULL)
 353                         goto out_domain;
 354         }
 355
 356         if (addr == NULL && mask == NULL) {
 357                 entry->def.cipso = doi_def;
 358                 entry->def.type = NETLBL_NLTYPE_CIPSOV4;
 359         } else if (addr != NULL && mask != NULL) {
 360                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 361                 if (addrmap == NULL)
 362                         goto out_addrmap;
 363                 INIT_LIST_HEAD(&addrmap->list4);
 364                 INIT_LIST_HEAD(&addrmap->list6);
 365
 366                 addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC);
 367                 if (addrinfo == NULL)
 368                         goto out_addrinfo;
 369                 addrinfo->def.cipso = doi_def;
 370                 addrinfo->def.type = NETLBL_NLTYPE_CIPSOV4;
 371                 addrinfo->list.addr = addr->s_addr & mask->s_addr;
 372                 addrinfo->list.mask = mask->s_addr;
 373                 addrinfo->list.valid = 1;
 374                 ret_val = netlbl_af4list_add(&addrinfo->list, &addrmap->list4);
 375                 if (ret_val != 0)
 376                         goto cfg_cipsov4_map_add_failure;
 377
 378                 entry->def.addrsel = addrmap;
 379                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 380         } else {
 381                 ret_val = -EINVAL;
 382                 goto out_addrmap;
 383         }
 384
 385         ret_val = netlbl_domhsh_add(entry, audit_info);
 386         if (ret_val != 0)
 387                 goto cfg_cipsov4_map_add_failure;
 388
 389         return 0;
 390
 391 cfg_cipsov4_map_add_failure:
 392         kfree(addrinfo);
 393 out_addrinfo:
 394         kfree(addrmap);
 395 out_addrmap:
 396         kfree(entry->domain);
 397 out_domain:
 398         kfree(entry);
 399 out_entry:
 400         cipso_v4_doi_putdef(doi_def);
 401         return ret_val;
 402 }
 403
 404 /*
 405  * Security Attribute Functions
 406  */
 407
 408 #define _CM_F_NONE      0x00000000
 409 #define _CM_F_ALLOC     0x00000001
 410 #define _CM_F_WALK      0x00000002
 411
 412 /**
 413  * _netlbl_secattr_catmap_getnode - Get a individual node from a catmap
 414  * @catmap: pointer to the category bitmap
 415  * @offset: the requested offset
 416  * @cm_flags: catmap flags, see _CM_F_*
 417  * @gfp_flags: memory allocation flags
 418  *
 419  * Description:
 420  * Iterate through the catmap looking for the node associated with @offset.
 421  * If the _CM_F_ALLOC flag is set in @cm_flags and there is no associated node,
 422  * one will be created and inserted into the catmap.  If the _CM_F_WALK flag is
 423  * set in @cm_flags and there is no associated node, the next highest node will
 424  * be returned.  Returns a pointer to the node on success, NULL on failure.
 425  *
 426  */
 427 static struct netlbl_lsm_secattr_catmap *_netlbl_secattr_catmap_getnode(
 428                                 struct netlbl_lsm_secattr_catmap **catmap,
 429                                 u32 offset,
 430                                 unsigned int cm_flags,
 431                                 gfp_t gfp_flags)
 432 {
 433         struct netlbl_lsm_secattr_catmap *iter = *catmap;
 434         struct netlbl_lsm_secattr_catmap *prev = NULL;
 435
 436         if (iter == NULL)
 437                 goto secattr_catmap_getnode_alloc;
 438         if (offset < iter->startbit)
 439                 goto secattr_catmap_getnode_walk;
 440         while (iter && offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 441                 prev = iter;
 442                 iter = iter->next;
 443         }
 444         if (iter == NULL || offset < iter->startbit)
 445                 goto secattr_catmap_getnode_walk;
 446
 447         return iter;
 448
 449 secattr_catmap_getnode_walk:
 450         if (cm_flags & _CM_F_WALK)
 451                 return iter;
 452 secattr_catmap_getnode_alloc:
 453         if (!(cm_flags & _CM_F_ALLOC))
 454                 return NULL;
 455
 456         iter = netlbl_secattr_catmap_alloc(gfp_flags);
 457         if (iter == NULL)
 458                 return NULL;
 459         iter->startbit = offset & ~(NETLBL_CATMAP_SIZE - 1);
 460
 461         if (prev == NULL) {
 462                 iter->next = *catmap;
 463                 *catmap = iter;
 464         } else {
 465                 iter->next = prev->next;
 466                 prev->next = iter;
 467         }
 468
 469         return iter;
 470 }
 471
 472 /**
 473  * netlbl_secattr_catmap_walk - Walk a LSM secattr catmap looking for a bit
 474  * @catmap: the category bitmap
 475  * @offset: the offset to start searching at, in bits
 476  *
 477  * Description:
 478  * This function walks a LSM secattr category bitmap starting at @offset and
 479  * returns the spot of the first set bit or -ENOENT if no bits are set.
 480  *
 481  */
 482 int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
 483                                u32 offset)
 484 {
 485         struct netlbl_lsm_secattr_catmap *iter = catmap;
 486         u32 idx;
 487         u32 bit;
 488         NETLBL_CATMAP_MAPTYPE bitmap;
 489
 490         iter = _netlbl_secattr_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 491         if (iter == NULL)
 492                 return -ENOENT;
 493         if (offset > iter->startbit) {
 494                 offset -= iter->startbit;
 495                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 496                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 497         } else {
 498                 idx = 0;
 499                 bit = 0;
 500         }
 501         bitmap = iter->bitmap[idx] >> bit;
 502
 503         for (;;) {
 504                 if (bitmap != 0) {
 505                         while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
 506                                 bitmap >>= 1;
 507                                 bit++;
 508                         }
 509                         return iter->startbit +
 510                                (NETLBL_CATMAP_MAPSIZE * idx) + bit;
 511                 }
 512                 if (++idx >= NETLBL_CATMAP_MAPCNT) {
 513                         if (iter->next != NULL) {
 514                                 iter = iter->next;
 515                                 idx = 0;
 516                         } else
 517                                 return -ENOENT;
 518                 }
 519                 bitmap = iter->bitmap[idx];
 520                 bit = 0;
 521         }
 522
 523         return -ENOENT;
 524 }
 525
 526 /**
 527  * netlbl_secattr_catmap_walk_rng - Find the end of a string of set bits
 528  * @catmap: the category bitmap
 529  * @offset: the offset to start searching at, in bits
 530  *
 531  * Description:
 532  * This function walks a LSM secattr category bitmap starting at @offset and
 533  * returns the spot of the first cleared bit or -ENOENT if the offset is past
 534  * the end of the bitmap.
 535  *
 536  */
 537 int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
 538                                    u32 offset)
 539 {
 540         struct netlbl_lsm_secattr_catmap *iter;
 541         struct netlbl_lsm_secattr_catmap *prev = NULL;
 542         u32 idx;
 543         u32 bit;
 544         NETLBL_CATMAP_MAPTYPE bitmask;
 545         NETLBL_CATMAP_MAPTYPE bitmap;
 546
 547         iter = _netlbl_secattr_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 548         if (iter == NULL)
 549                 return -ENOENT;
 550         if (offset > iter->startbit) {
 551                 offset -= iter->startbit;
 552                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 553                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 554         } else {
 555                 idx = 0;
 556                 bit = 0;
 557         }
 558         bitmask = NETLBL_CATMAP_BIT << bit;
 559
 560         for (;;) {
 561                 bitmap = iter->bitmap[idx];
 562                 while (bitmask != 0 && (bitmap & bitmask) != 0) {
 563                         bitmask <<= 1;
 564                         bit++;
 565                 }
 566
 567                 if (prev && idx == 0 && bit == 0)
 568                         return prev->startbit + NETLBL_CATMAP_SIZE - 1;
 569                 else if (bitmask != 0)
 570                         return iter->startbit +
 571                                 (NETLBL_CATMAP_MAPSIZE * idx) + bit - 1;
 572                 else if (++idx >= NETLBL_CATMAP_MAPCNT) {
 573                         if (iter->next == NULL)
 574                                 return iter->startbit + NETLBL_CATMAP_SIZE - 1;
 575                         prev = iter;
 576                         iter = iter->next;
 577                         idx = 0;
 578                 }
 579                 bitmask = NETLBL_CATMAP_BIT;
 580                 bit = 0;
 581         }
 582
 583         return -ENOENT;
 584 }
 585
 586 /**
 587  * netlbl_secattr_catmap_getlong - Export an unsigned long bitmap
 588  * @catmap: pointer to the category bitmap
 589  * @offset: pointer to the requested offset
 590  * @bitmap: the exported bitmap
 591  *
 592  * Description:
 593  * Export a bitmap with an offset greater than or equal to @offset and return
 594  * it in @bitmap.  The @offset must be aligned to an unsigned long and will be
 595  * updated on return if different from what was requested; if the catmap is
 596  * empty at the requested offset and beyond, the @offset is set to (u32)-1.
 597  * Returns zero on sucess, negative values on failure.
 598  *
 599  */
 600 int netlbl_secattr_catmap_getlong(struct netlbl_lsm_secattr_catmap *catmap,
 601                                   u32 *offset,
 602                                   unsigned long *bitmap)
 603 {
 604         struct netlbl_lsm_secattr_catmap *iter;
 605         u32 off = *offset;
 606         u32 idx;
 607
 608         /* only allow aligned offsets */
 609         if ((off & (BITS_PER_LONG - 1)) != 0)
 610                 return -EINVAL;
 611
 612         if (off < catmap->startbit) {
 613                 off = catmap->startbit;
 614                 *offset = off;
 615         }
 616         iter = _netlbl_secattr_catmap_getnode(&catmap, off, _CM_F_NONE, 0);
 617         if (iter == NULL) {
 618                 *offset = (u32)-1;
 619                 return 0;
 620         }
 621
 622         if (off < iter->startbit) {
 623                 off = iter->startbit;
 624                 *offset = off;
 625         } else
 626                 off -= iter->startbit;
 627
 628         idx = off / NETLBL_CATMAP_MAPSIZE;
 629         *bitmap = iter->bitmap[idx] >> (off % NETLBL_CATMAP_SIZE);
 630
 631         return 0;
 632 }
 633
 634 /**
 635  * netlbl_secattr_catmap_setbit - Set a bit in a LSM secattr catmap
 636  * @catmap: pointer to the category bitmap
 637  * @bit: the bit to set
 638  * @flags: memory allocation flags
 639  *
 640  * Description:
 641  * Set the bit specified by @bit in @catmap.  Returns zero on success,
 642  * negative values on failure.
 643  *
 644  */
 645 int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap **catmap,
 646                                  u32 bit,
 647                                  gfp_t flags)
 648 {
 649         struct netlbl_lsm_secattr_catmap *iter;
 650         u32 idx;
 651
 652         iter = _netlbl_secattr_catmap_getnode(catmap, bit, _CM_F_ALLOC, flags);
 653         if (iter == NULL)
 654                 return -ENOMEM;
 655
 656         bit -= iter->startbit;
 657         idx = bit / NETLBL_CATMAP_MAPSIZE;
 658         iter->bitmap[idx] |= NETLBL_CATMAP_BIT << (bit % NETLBL_CATMAP_MAPSIZE);
 659
 660         return 0;
 661 }
 662
 663 /**
 664  * netlbl_secattr_catmap_setrng - Set a range of bits in a LSM secattr catmap
 665  * @catmap: pointer to the category bitmap
 666  * @start: the starting bit
 667  * @end: the last bit in the string
 668  * @flags: memory allocation flags
 669  *
 670  * Description:
 671  * Set a range of bits, starting at @start and ending with @end.  Returns zero
 672  * on success, negative values on failure.
 673  *
 674  */
 675 int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap **catmap,
 676                                  u32 start,
 677                                  u32 end,
 678                                  gfp_t flags)
 679 {
 680         int rc = 0;
 681         u32 spot = start;
 682
 683         while (rc == 0 && spot <= end) {
 684                 if (((spot & (BITS_PER_LONG - 1)) != 0) &&
 685                     ((end - spot) > BITS_PER_LONG)) {
 686                         rc = netlbl_secattr_catmap_setlong(catmap,
 687                                                            spot,
 688                                                            (unsigned long)-1,
 689                                                            flags);
 690                         spot += BITS_PER_LONG;
 691                 } else
 692                         rc = netlbl_secattr_catmap_setbit(catmap,
 693                                                           spot++,
 694                                                           flags);
 695         }
 696
 697         return rc;
 698 }
 699
 700 /**
 701  * netlbl_secattr_catmap_setlong - Import an unsigned long bitmap
 702  * @catmap: pointer to the category bitmap
 703  * @offset: offset to the start of the imported bitmap
 704  * @bitmap: the bitmap to import
 705  * @flags: memory allocation flags
 706  *
 707  * Description:
 708  * Import the bitmap specified in @bitmap into @catmap, using the offset
 709  * in @offset.  The offset must be aligned to an unsigned long.  Returns zero
 710  * on success, negative values on failure.
 711  *
 712  */
 713 int netlbl_secattr_catmap_setlong(struct netlbl_lsm_secattr_catmap **catmap,
 714                                   u32 offset,
 715                                   unsigned long bitmap,
 716                                   gfp_t flags)
 717 {
 718         struct netlbl_lsm_secattr_catmap *iter;
 719         u32 idx;
 720
 721         /* only allow aligned offsets */
 722         if ((offset & (BITS_PER_LONG - 1)) != 0)
 723                 return -EINVAL;
 724
 725         iter = _netlbl_secattr_catmap_getnode(catmap,
 726                                               offset, _CM_F_ALLOC, flags);
 727         if (iter == NULL)
 728                 return -ENOMEM;
 729
 730         offset -= iter->startbit;
 731         idx = offset / NETLBL_CATMAP_MAPSIZE;
 732         iter->bitmap[idx] |= bitmap << (offset % NETLBL_CATMAP_MAPSIZE);
 733
 734         return 0;
 735 }
 736
 737 /*
 738  * LSM Functions
 739  */
 740
 741 /**
 742  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
 743  *
 744  * Description:
 745  * The LSM can use this function to determine if it should use NetLabel
 746  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
 747  * considered to be enabled when it's configuration contains a valid setup for
 748  * at least one labeled protocol (i.e. NetLabel can understand incoming
 749  * labeled packets of at least one type); otherwise NetLabel is considered to
 750  * be disabled.
 751  *
 752  */
 753 int netlbl_enabled(void)
 754 {
 755         /* At some point we probably want to expose this mechanism to the user
 756          * as well so that admins can toggle NetLabel regardless of the
 757          * configuration */
 758         return (atomic_read(&netlabel_mgmt_protocount) > 0);
 759 }
 760
 761 /**
 762  * netlbl_sock_setattr - Label a socket using the correct protocol
 763  * @sk: the socket to label
 764  * @family: protocol family
 765  * @secattr: the security attributes
 766  *
 767  * Description:
 768  * Attach the correct label to the given socket using the security attributes
 769  * specified in @secattr.  This function requires exclusive access to @sk,
 770  * which means it either needs to be in the process of being created or locked.
 771  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
 772  * network address selectors (can't blindly label the socket), and negative
 773  * values on all other failures.
 774  *
 775  */
 776 int netlbl_sock_setattr(struct sock *sk,
 777                         u16 family,
 778                         const struct netlbl_lsm_secattr *secattr)
 779 {
 780         int ret_val;
 781         struct netlbl_dom_map *dom_entry;
 782
 783         rcu_read_lock();
 784         dom_entry = netlbl_domhsh_getentry(secattr->domain);
 785         if (dom_entry == NULL) {
 786                 ret_val = -ENOENT;
 787                 goto socket_setattr_return;
 788         }
 789         switch (family) {
 790         case AF_INET:
 791                 switch (dom_entry->def.type) {
 792                 case NETLBL_NLTYPE_ADDRSELECT:
 793                         ret_val = -EDESTADDRREQ;
 794                         break;
 795                 case NETLBL_NLTYPE_CIPSOV4:
 796                         ret_val = cipso_v4_sock_setattr(sk,
 797                                                         dom_entry->def.cipso,
 798                                                         secattr);
 799                         break;
 800                 case NETLBL_NLTYPE_UNLABELED:
 801                         ret_val = 0;
 802                         break;
 803                 default:
 804                         ret_val = -ENOENT;
 805                 }
 806                 break;
 807 #if IS_ENABLED(CONFIG_IPV6)
 808         case AF_INET6:
 809                 /* since we don't support any IPv6 labeling protocols right
 810                  * now we can optimize everything away until we do */
 811                 ret_val = 0;
 812                 break;
 813 #endif /* IPv6 */
 814         default:
 815                 ret_val = -EPROTONOSUPPORT;
 816         }
 817
 818 socket_setattr_return:
 819         rcu_read_unlock();
 820         return ret_val;
 821 }
 822
 823 /**
 824  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
 825  * @sk: the socket
 826  *
 827  * Description:
 828  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
 829  * ensuring that @sk is locked.
 830  *
 831  */
 832 void netlbl_sock_delattr(struct sock *sk)
 833 {
 834         cipso_v4_sock_delattr(sk);
 835 }
 836
 837 /**
 838  * netlbl_sock_getattr - Determine the security attributes of a sock
 839  * @sk: the sock
 840  * @secattr: the security attributes
 841  *
 842  * Description:
 843  * Examines the given sock to see if any NetLabel style labeling has been
 844  * applied to the sock, if so it parses the socket label and returns the
 845  * security attributes in @secattr.  Returns zero on success, negative values
 846  * on failure.
 847  *
 848  */
 849 int netlbl_sock_getattr(struct sock *sk,
 850                         struct netlbl_lsm_secattr *secattr)
 851 {
 852         int ret_val;
 853
 854         switch (sk->sk_family) {
 855         case AF_INET:
 856                 ret_val = cipso_v4_sock_getattr(sk, secattr);
 857                 break;
 858 #if IS_ENABLED(CONFIG_IPV6)
 859         case AF_INET6:
 860                 ret_val = -ENOMSG;
 861                 break;
 862 #endif /* IPv6 */
 863         default:
 864                 ret_val = -EPROTONOSUPPORT;
 865         }
 866
 867         return ret_val;
 868 }
 869
 870 /**
 871  * netlbl_conn_setattr - Label a connected socket using the correct protocol
 872  * @sk: the socket to label
 873  * @addr: the destination address
 874  * @secattr: the security attributes
 875  *
 876  * Description:
 877  * Attach the correct label to the given connected socket using the security
 878  * attributes specified in @secattr.  The caller is responsible for ensuring
 879  * that @sk is locked.  Returns zero on success, negative values on failure.
 880  *
 881  */
 882 int netlbl_conn_setattr(struct sock *sk,
 883                         struct sockaddr *addr,
 884                         const struct netlbl_lsm_secattr *secattr)
 885 {
 886         int ret_val;
 887         struct sockaddr_in *addr4;
 888         struct netlbl_dommap_def *entry;
 889
 890         rcu_read_lock();
 891         switch (addr->sa_family) {
 892         case AF_INET:
 893                 addr4 = (struct sockaddr_in *)addr;
 894                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
 895                                                    addr4->sin_addr.s_addr);
 896                 if (entry == NULL) {
 897                         ret_val = -ENOENT;
 898                         goto conn_setattr_return;
 899                 }
 900                 switch (entry->type) {
 901                 case NETLBL_NLTYPE_CIPSOV4:
 902                         ret_val = cipso_v4_sock_setattr(sk,
 903                                                         entry->cipso, secattr);
 904                         break;
 905                 case NETLBL_NLTYPE_UNLABELED:
 906                         /* just delete the protocols we support for right now
 907                          * but we could remove other protocols if needed */
 908                         cipso_v4_sock_delattr(sk);
 909                         ret_val = 0;
 910                         break;
 911                 default:
 912                         ret_val = -ENOENT;
 913                 }
 914                 break;
 915 #if IS_ENABLED(CONFIG_IPV6)
 916         case AF_INET6:
 917                 /* since we don't support any IPv6 labeling protocols right
 918                  * now we can optimize everything away until we do */
 919                 ret_val = 0;
 920                 break;
 921 #endif /* IPv6 */
 922         default:
 923                 ret_val = -EPROTONOSUPPORT;
 924         }
 925
 926 conn_setattr_return:
 927         rcu_read_unlock();
 928         return ret_val;
 929 }
 930
 931 /**
 932  * netlbl_req_setattr - Label a request socket using the correct protocol
 933  * @req: the request socket to label
 934  * @secattr: the security attributes
 935  *
 936  * Description:
 937  * Attach the correct label to the given socket using the security attributes
 938  * specified in @secattr.  Returns zero on success, negative values on failure.
 939  *
 940  */
 941 int netlbl_req_setattr(struct request_sock *req,
 942                        const struct netlbl_lsm_secattr *secattr)
 943 {
 944         int ret_val;
 945         struct netlbl_dommap_def *entry;
 946
 947         rcu_read_lock();
 948         switch (req->rsk_ops->family) {
 949         case AF_INET:
 950                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
 951                                                    inet_rsk(req)->ir_rmt_addr);
 952                 if (entry == NULL) {
 953                         ret_val = -ENOENT;
 954                         goto req_setattr_return;
 955                 }
 956                 switch (entry->type) {
 957                 case NETLBL_NLTYPE_CIPSOV4:
 958                         ret_val = cipso_v4_req_setattr(req,
 959                                                        entry->cipso, secattr);
 960                         break;
 961                 case NETLBL_NLTYPE_UNLABELED:
 962                         /* just delete the protocols we support for right now
 963                          * but we could remove other protocols if needed */
 964                         cipso_v4_req_delattr(req);
 965                         ret_val = 0;
 966                         break;
 967                 default:
 968                         ret_val = -ENOENT;
 969                 }
 970                 break;
 971 #if IS_ENABLED(CONFIG_IPV6)
 972         case AF_INET6:
 973                 /* since we don't support any IPv6 labeling protocols right
 974                  * now we can optimize everything away until we do */
 975                 ret_val = 0;
 976                 break;
 977 #endif /* IPv6 */
 978         default:
 979                 ret_val = -EPROTONOSUPPORT;
 980         }
 981
 982 req_setattr_return:
 983         rcu_read_unlock();
 984         return ret_val;
 985 }
 986
 987 /**
 988 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
 989 * @req: the socket
 990 *
 991 * Description:
 992 * Remove all the NetLabel labeling from @req.
 993 *
 994 */
 995 void netlbl_req_delattr(struct request_sock *req)
 996 {
 997         cipso_v4_req_delattr(req);
 998 }
 999
1000 /**
1001  * netlbl_skbuff_setattr - Label a packet using the correct protocol
1002  * @skb: the packet
1003  * @family: protocol family
1004  * @secattr: the security attributes
1005  *
1006  * Description:
1007  * Attach the correct label to the given packet using the security attributes
1008  * specified in @secattr.  Returns zero on success, negative values on failure.
1009  *
1010  */
1011 int netlbl_skbuff_setattr(struct sk_buff *skb,
1012                           u16 family,
1013                           const struct netlbl_lsm_secattr *secattr)
1014 {
1015         int ret_val;
1016         struct iphdr *hdr4;
1017         struct netlbl_dommap_def *entry;
1018
1019         rcu_read_lock();
1020         switch (family) {
1021         case AF_INET:
1022                 hdr4 = ip_hdr(skb);
1023                 entry = netlbl_domhsh_getentry_af4(secattr->domain,hdr4->daddr);
1024                 if (entry == NULL) {
1025                         ret_val = -ENOENT;
1026                         goto skbuff_setattr_return;
1027                 }
1028                 switch (entry->type) {
1029                 case NETLBL_NLTYPE_CIPSOV4:
1030                         ret_val = cipso_v4_skbuff_setattr(skb, entry->cipso,
1031                                                           secattr);
1032                         break;
1033                 case NETLBL_NLTYPE_UNLABELED:
1034                         /* just delete the protocols we support for right now
1035                          * but we could remove other protocols if needed */
1036                         ret_val = cipso_v4_skbuff_delattr(skb);
1037                         break;
1038                 default:
1039                         ret_val = -ENOENT;
1040                 }
1041                 break;
1042 #if IS_ENABLED(CONFIG_IPV6)
1043         case AF_INET6:
1044                 /* since we don't support any IPv6 labeling protocols right
1045                  * now we can optimize everything away until we do */
1046                 ret_val = 0;
1047                 break;
1048 #endif /* IPv6 */
1049         default:
1050                 ret_val = -EPROTONOSUPPORT;
1051         }
1052
1053 skbuff_setattr_return:
1054         rcu_read_unlock();
1055         return ret_val;
1056 }
1057
1058 /**
1059  * netlbl_skbuff_getattr - Determine the security attributes of a packet
1060  * @skb: the packet
1061  * @family: protocol family
1062  * @secattr: the security attributes
1063  *
1064  * Description:
1065  * Examines the given packet to see if a recognized form of packet labeling
1066  * is present, if so it parses the packet label and returns the security
1067  * attributes in @secattr.  Returns zero on success, negative values on
1068  * failure.
1069  *
1070  */
1071 int netlbl_skbuff_getattr(const struct sk_buff *skb,
1072                           u16 family,
1073                           struct netlbl_lsm_secattr *secattr)
1074 {
1075         switch (family) {
1076         case AF_INET:
1077                 if (CIPSO_V4_OPTEXIST(skb) &&
1078                     cipso_v4_skbuff_getattr(skb, secattr) == 0)
1079                         return 0;
1080                 break;
1081 #if IS_ENABLED(CONFIG_IPV6)
1082         case AF_INET6:
1083                 break;
1084 #endif /* IPv6 */
1085         }
1086
1087         return netlbl_unlabel_getattr(skb, family, secattr);
1088 }
1089
1090 /**
1091  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
1092  * @skb: the packet
1093  * @error: the error code
1094  * @gateway: true if host is acting as a gateway, false otherwise
1095  *
1096  * Description:
1097  * Deal with a LSM problem when handling the packet in @skb, typically this is
1098  * a permission denied problem (-EACCES).  The correct action is determined
1099  * according to the packet's labeling protocol.
1100  *
1101  */
1102 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
1103 {
1104         if (CIPSO_V4_OPTEXIST(skb))
1105                 cipso_v4_error(skb, error, gateway);
1106 }
1107
1108 /**
1109  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
1110  *
1111  * Description:
1112  * For all of the NetLabel protocols that support some form of label mapping
1113  * cache, invalidate the cache.  Returns zero on success, negative values on
1114  * error.
1115  *
1116  */
1117 void netlbl_cache_invalidate(void)
1118 {
1119         cipso_v4_cache_invalidate();
1120 }
1121
1122 /**
1123  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1124  * @skb: the packet
1125  * @secattr: the packet's security attributes
1126  *
1127  * Description:
1128  * Add the LSM security attributes for the given packet to the underlying
1129  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1130  * values on error.
1131  *
1132  */
1133 int netlbl_cache_add(const struct sk_buff *skb,
1134                      const struct netlbl_lsm_secattr *secattr)
1135 {
1136         if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1137                 return -ENOMSG;
1138
1139         if (CIPSO_V4_OPTEXIST(skb))
1140                 return cipso_v4_cache_add(skb, secattr);
1141
1142         return -ENOMSG;
1143 }
1144
1145 /*
1146  * Protocol Engine Functions
1147  */
1148
1149 /**
1150  * netlbl_audit_start - Start an audit message
1151  * @type: audit message type
1152  * @audit_info: NetLabel audit information
1153  *
1154  * Description:
1155  * Start an audit message using the type specified in @type and fill the audit
1156  * message with some fields common to all NetLabel audit messages.  This
1157  * function should only be used by protocol engines, not LSMs.  Returns a
1158  * pointer to the audit buffer on success, NULL on failure.
1159  *
1160  */
1161 struct audit_buffer *netlbl_audit_start(int type,
1162                                         struct netlbl_audit *audit_info)
1163 {
1164         return netlbl_audit_start_common(type, audit_info);
1165 }
1166
1167 /*
1168  * Setup Functions
1169  */
1170
1171 /**
1172  * netlbl_init - Initialize NetLabel
1173  *
1174  * Description:
1175  * Perform the required NetLabel initialization before first use.
1176  *
1177  */
1178 static int __init netlbl_init(void)
1179 {
1180         int ret_val;
1181
1182         printk(KERN_INFO "NetLabel: Initializing\n");
1183         printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1184                (1 << NETLBL_DOMHSH_BITSIZE));
1185         printk(KERN_INFO "NetLabel:  protocols ="
1186                " UNLABELED"
1187                " CIPSOv4"
1188                "\n");
1189
1190         ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1191         if (ret_val != 0)
1192                 goto init_failure;
1193
1194         ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1195         if (ret_val != 0)
1196                 goto init_failure;
1197
1198         ret_val = netlbl_netlink_init();
1199         if (ret_val != 0)
1200                 goto init_failure;
1201
1202         ret_val = netlbl_unlabel_defconf();
1203         if (ret_val != 0)
1204                 goto init_failure;
1205         printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1206
1207         return 0;
1208
1209 init_failure:
1210         panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1211 }
1212
1213 subsys_initcall(netlbl_init);