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 <net/calipso.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_calipso.h"
  48 #include "netlabel_user.h"
  49 #include "netlabel_mgmt.h"
  50 #include "netlabel_addrlist.h"
  51
  52 /*
  53  * Configuration Functions
  54  */
  55
  56 /**
  57  * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping
  58  * @domain: the domain mapping to remove
  59  * @family: address family
  60  * @addr: IP address
  61  * @mask: IP address mask
  62  * @audit_info: NetLabel audit information
  63  *
  64  * Description:
  65  * Removes a NetLabel/LSM domain mapping.  A @domain value of NULL causes the
  66  * default domain mapping to be removed.  Returns zero on success, negative
  67  * values on failure.
  68  *
  69  */
  70 int netlbl_cfg_map_del(const char *domain,
  71                        u16 family,
  72                        const void *addr,
  73                        const void *mask,
  74                        struct netlbl_audit *audit_info)
  75 {
  76         if (addr == NULL && mask == NULL) {
  77                 return netlbl_domhsh_remove(domain, family, audit_info);
  78         } else if (addr != NULL && mask != NULL) {
  79                 switch (family) {
  80                 case AF_INET:
  81                         return netlbl_domhsh_remove_af4(domain, addr, mask,
  82                                                         audit_info);
  83                 default:
  84                         return -EPFNOSUPPORT;
  85                 }
  86         } else
  87                 return -EINVAL;
  88 }
  89
  90 /**
  91  * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping
  92  * @domain: the domain mapping to add
  93  * @family: address family
  94  * @addr: IP address
  95  * @mask: IP address mask
  96  * @audit_info: NetLabel audit information
  97  *
  98  * Description:
  99  * Adds a new unlabeled NetLabel/LSM domain mapping.  A @domain value of NULL
 100  * causes a new default domain mapping to be added.  Returns zero on success,
 101  * negative values on failure.
 102  *
 103  */
 104 int netlbl_cfg_unlbl_map_add(const char *domain,
 105                              u16 family,
 106                              const void *addr,
 107                              const void *mask,
 108                              struct netlbl_audit *audit_info)
 109 {
 110         int ret_val = -ENOMEM;
 111         struct netlbl_dom_map *entry;
 112         struct netlbl_domaddr_map *addrmap = NULL;
 113         struct netlbl_domaddr4_map *map4 = NULL;
 114         struct netlbl_domaddr6_map *map6 = NULL;
 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         entry->family = family;
 125
 126         if (addr == NULL && mask == NULL)
 127                 entry->def.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                         const struct in_addr *addr4 = addr;
 138                         const struct in_addr *mask4 = mask;
 139                         map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
 140                         if (map4 == NULL)
 141                                 goto cfg_unlbl_map_add_failure;
 142                         map4->def.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                         }
 152 #if IS_ENABLED(CONFIG_IPV6)
 153                 case AF_INET6: {
 154                         const struct in6_addr *addr6 = addr;
 155                         const struct in6_addr *mask6 = mask;
 156                         map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
 157                         if (map6 == NULL)
 158                                 goto cfg_unlbl_map_add_failure;
 159                         map6->def.type = NETLBL_NLTYPE_UNLABELED;
 160                         map6->list.addr = *addr6;
 161                         map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
 162                         map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
 163                         map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
 164                         map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
 165                         map6->list.mask = *mask6;
 166                         map6->list.valid = 1;
 167                         ret_val = netlbl_af6list_add(&map6->list,
 168                                                      &addrmap->list6);
 169                         if (ret_val != 0)
 170                                 goto cfg_unlbl_map_add_failure;
 171                         break;
 172                         }
 173 #endif /* IPv6 */
 174                 default:
 175                         goto cfg_unlbl_map_add_failure;
 176                 }
 177
 178                 entry->def.addrsel = addrmap;
 179                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 180         } else {
 181                 ret_val = -EINVAL;
 182                 goto cfg_unlbl_map_add_failure;
 183         }
 184
 185         ret_val = netlbl_domhsh_add(entry, audit_info);
 186         if (ret_val != 0)
 187                 goto cfg_unlbl_map_add_failure;
 188
 189         return 0;
 190
 191 cfg_unlbl_map_add_failure:
 192         kfree(entry->domain);
 193         kfree(entry);
 194         kfree(addrmap);
 195         kfree(map4);
 196         kfree(map6);
 197         return ret_val;
 198 }
 199
 200
 201 /**
 202  * netlbl_cfg_unlbl_static_add - Adds a new static label
 203  * @net: network namespace
 204  * @dev_name: interface name
 205  * @addr: IP address in network byte order (struct in[6]_addr)
 206  * @mask: address mask in network byte order (struct in[6]_addr)
 207  * @family: address family
 208  * @secid: LSM secid value for the entry
 209  * @audit_info: NetLabel audit information
 210  *
 211  * Description:
 212  * Adds a new NetLabel static label to be used when protocol provided labels
 213  * are not present on incoming traffic.  If @dev_name is NULL then the default
 214  * interface will be used.  Returns zero on success, negative values on failure.
 215  *
 216  */
 217 int netlbl_cfg_unlbl_static_add(struct net *net,
 218                                 const char *dev_name,
 219                                 const void *addr,
 220                                 const void *mask,
 221                                 u16 family,
 222                                 u32 secid,
 223                                 struct netlbl_audit *audit_info)
 224 {
 225         u32 addr_len;
 226
 227         switch (family) {
 228         case AF_INET:
 229                 addr_len = sizeof(struct in_addr);
 230                 break;
 231 #if IS_ENABLED(CONFIG_IPV6)
 232         case AF_INET6:
 233                 addr_len = sizeof(struct in6_addr);
 234                 break;
 235 #endif /* IPv6 */
 236         default:
 237                 return -EPFNOSUPPORT;
 238         }
 239
 240         return netlbl_unlhsh_add(net,
 241                                  dev_name, addr, mask, addr_len,
 242                                  secid, audit_info);
 243 }
 244
 245 /**
 246  * netlbl_cfg_unlbl_static_del - Removes an existing static label
 247  * @net: network namespace
 248  * @dev_name: interface name
 249  * @addr: IP address in network byte order (struct in[6]_addr)
 250  * @mask: address mask in network byte order (struct in[6]_addr)
 251  * @family: address family
 252  * @audit_info: NetLabel audit information
 253  *
 254  * Description:
 255  * Removes an existing NetLabel static label used when protocol provided labels
 256  * are not present on incoming traffic.  If @dev_name is NULL then the default
 257  * interface will be used.  Returns zero on success, negative values on failure.
 258  *
 259  */
 260 int netlbl_cfg_unlbl_static_del(struct net *net,
 261                                 const char *dev_name,
 262                                 const void *addr,
 263                                 const void *mask,
 264                                 u16 family,
 265                                 struct netlbl_audit *audit_info)
 266 {
 267         u32 addr_len;
 268
 269         switch (family) {
 270         case AF_INET:
 271                 addr_len = sizeof(struct in_addr);
 272                 break;
 273 #if IS_ENABLED(CONFIG_IPV6)
 274         case AF_INET6:
 275                 addr_len = sizeof(struct in6_addr);
 276                 break;
 277 #endif /* IPv6 */
 278         default:
 279                 return -EPFNOSUPPORT;
 280         }
 281
 282         return netlbl_unlhsh_remove(net,
 283                                     dev_name, addr, mask, addr_len,
 284                                     audit_info);
 285 }
 286
 287 /**
 288  * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition
 289  * @doi_def: CIPSO DOI definition
 290  * @audit_info: NetLabel audit information
 291  *
 292  * Description:
 293  * Add a new CIPSO DOI definition as defined by @doi_def.  Returns zero on
 294  * success and negative values on failure.
 295  *
 296  */
 297 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
 298                            struct netlbl_audit *audit_info)
 299 {
 300         return cipso_v4_doi_add(doi_def, audit_info);
 301 }
 302
 303 /**
 304  * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition
 305  * @doi: CIPSO DOI
 306  * @audit_info: NetLabel audit information
 307  *
 308  * Description:
 309  * Remove an existing CIPSO DOI definition matching @doi.  Returns zero on
 310  * success and negative values on failure.
 311  *
 312  */
 313 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info)
 314 {
 315         cipso_v4_doi_remove(doi, audit_info);
 316 }
 317
 318 /**
 319  * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping
 320  * @doi: the CIPSO DOI
 321  * @domain: the domain mapping to add
 322  * @addr: IP address
 323  * @mask: IP address mask
 324  * @audit_info: NetLabel audit information
 325  *
 326  * Description:
 327  * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel
 328  * subsystem.  A @domain value of NULL adds a new default domain mapping.
 329  * Returns zero on success, negative values on failure.
 330  *
 331  */
 332 int netlbl_cfg_cipsov4_map_add(u32 doi,
 333                                const char *domain,
 334                                const struct in_addr *addr,
 335                                const struct in_addr *mask,
 336                                struct netlbl_audit *audit_info)
 337 {
 338         int ret_val = -ENOMEM;
 339         struct cipso_v4_doi *doi_def;
 340         struct netlbl_dom_map *entry;
 341         struct netlbl_domaddr_map *addrmap = NULL;
 342         struct netlbl_domaddr4_map *addrinfo = NULL;
 343
 344         doi_def = cipso_v4_doi_getdef(doi);
 345         if (doi_def == NULL)
 346                 return -ENOENT;
 347
 348         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 349         if (entry == NULL)
 350                 goto out_entry;
 351         entry->family = AF_INET;
 352         if (domain != NULL) {
 353                 entry->domain = kstrdup(domain, GFP_ATOMIC);
 354                 if (entry->domain == NULL)
 355                         goto out_domain;
 356         }
 357
 358         if (addr == NULL && mask == NULL) {
 359                 entry->def.cipso = doi_def;
 360                 entry->def.type = NETLBL_NLTYPE_CIPSOV4;
 361         } else if (addr != NULL && mask != NULL) {
 362                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 363                 if (addrmap == NULL)
 364                         goto out_addrmap;
 365                 INIT_LIST_HEAD(&addrmap->list4);
 366                 INIT_LIST_HEAD(&addrmap->list6);
 367
 368                 addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC);
 369                 if (addrinfo == NULL)
 370                         goto out_addrinfo;
 371                 addrinfo->def.cipso = doi_def;
 372                 addrinfo->def.type = NETLBL_NLTYPE_CIPSOV4;
 373                 addrinfo->list.addr = addr->s_addr & mask->s_addr;
 374                 addrinfo->list.mask = mask->s_addr;
 375                 addrinfo->list.valid = 1;
 376                 ret_val = netlbl_af4list_add(&addrinfo->list, &addrmap->list4);
 377                 if (ret_val != 0)
 378                         goto cfg_cipsov4_map_add_failure;
 379
 380                 entry->def.addrsel = addrmap;
 381                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 382         } else {
 383                 ret_val = -EINVAL;
 384                 goto out_addrmap;
 385         }
 386
 387         ret_val = netlbl_domhsh_add(entry, audit_info);
 388         if (ret_val != 0)
 389                 goto cfg_cipsov4_map_add_failure;
 390
 391         return 0;
 392
 393 cfg_cipsov4_map_add_failure:
 394         kfree(addrinfo);
 395 out_addrinfo:
 396         kfree(addrmap);
 397 out_addrmap:
 398         kfree(entry->domain);
 399 out_domain:
 400         kfree(entry);
 401 out_entry:
 402         cipso_v4_doi_putdef(doi_def);
 403         return ret_val;
 404 }
 405
 406 /*
 407  * Security Attribute Functions
 408  */
 409
 410 #define _CM_F_NONE      0x00000000
 411 #define _CM_F_ALLOC     0x00000001
 412 #define _CM_F_WALK      0x00000002
 413
 414 /**
 415  * _netlbl_catmap_getnode - Get a individual node from a catmap
 416  * @catmap: pointer to the category bitmap
 417  * @offset: the requested offset
 418  * @cm_flags: catmap flags, see _CM_F_*
 419  * @gfp_flags: memory allocation flags
 420  *
 421  * Description:
 422  * Iterate through the catmap looking for the node associated with @offset.
 423  * If the _CM_F_ALLOC flag is set in @cm_flags and there is no associated node,
 424  * one will be created and inserted into the catmap.  If the _CM_F_WALK flag is
 425  * set in @cm_flags and there is no associated node, the next highest node will
 426  * be returned.  Returns a pointer to the node on success, NULL on failure.
 427  *
 428  */
 429 static struct netlbl_lsm_catmap *_netlbl_catmap_getnode(
 430                                              struct netlbl_lsm_catmap **catmap,
 431                                              u32 offset,
 432                                              unsigned int cm_flags,
 433                                              gfp_t gfp_flags)
 434 {
 435         struct netlbl_lsm_catmap *iter = *catmap;
 436         struct netlbl_lsm_catmap *prev = NULL;
 437
 438         if (iter == NULL)
 439                 goto catmap_getnode_alloc;
 440         if (offset < iter->startbit)
 441                 goto catmap_getnode_walk;
 442         while (iter && offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
 443                 prev = iter;
 444                 iter = iter->next;
 445         }
 446         if (iter == NULL || offset < iter->startbit)
 447                 goto catmap_getnode_walk;
 448
 449         return iter;
 450
 451 catmap_getnode_walk:
 452         if (cm_flags & _CM_F_WALK)
 453                 return iter;
 454 catmap_getnode_alloc:
 455         if (!(cm_flags & _CM_F_ALLOC))
 456                 return NULL;
 457
 458         iter = netlbl_catmap_alloc(gfp_flags);
 459         if (iter == NULL)
 460                 return NULL;
 461         iter->startbit = offset & ~(NETLBL_CATMAP_SIZE - 1);
 462
 463         if (prev == NULL) {
 464                 iter->next = *catmap;
 465                 *catmap = iter;
 466         } else {
 467                 iter->next = prev->next;
 468                 prev->next = iter;
 469         }
 470
 471         return iter;
 472 }
 473
 474 /**
 475  * netlbl_catmap_walk - Walk a LSM secattr catmap looking for a bit
 476  * @catmap: the category bitmap
 477  * @offset: the offset to start searching at, in bits
 478  *
 479  * Description:
 480  * This function walks a LSM secattr category bitmap starting at @offset and
 481  * returns the spot of the first set bit or -ENOENT if no bits are set.
 482  *
 483  */
 484 int netlbl_catmap_walk(struct netlbl_lsm_catmap *catmap, u32 offset)
 485 {
 486         struct netlbl_lsm_catmap *iter = catmap;
 487         u32 idx;
 488         u32 bit;
 489         NETLBL_CATMAP_MAPTYPE bitmap;
 490
 491         iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 492         if (iter == NULL)
 493                 return -ENOENT;
 494         if (offset > iter->startbit) {
 495                 offset -= iter->startbit;
 496                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 497                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 498         } else {
 499                 idx = 0;
 500                 bit = 0;
 501         }
 502         bitmap = iter->bitmap[idx] >> bit;
 503
 504         for (;;) {
 505                 if (bitmap != 0) {
 506                         while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
 507                                 bitmap >>= 1;
 508                                 bit++;
 509                         }
 510                         return iter->startbit +
 511                                (NETLBL_CATMAP_MAPSIZE * idx) + bit;
 512                 }
 513                 if (++idx >= NETLBL_CATMAP_MAPCNT) {
 514                         if (iter->next != NULL) {
 515                                 iter = iter->next;
 516                                 idx = 0;
 517                         } else
 518                                 return -ENOENT;
 519                 }
 520                 bitmap = iter->bitmap[idx];
 521                 bit = 0;
 522         }
 523
 524         return -ENOENT;
 525 }
 526 EXPORT_SYMBOL(netlbl_catmap_walk);
 527
 528 /**
 529  * netlbl_catmap_walkrng - Find the end of a string of set bits
 530  * @catmap: the category bitmap
 531  * @offset: the offset to start searching at, in bits
 532  *
 533  * Description:
 534  * This function walks a LSM secattr category bitmap starting at @offset and
 535  * returns the spot of the first cleared bit or -ENOENT if the offset is past
 536  * the end of the bitmap.
 537  *
 538  */
 539 int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap, u32 offset)
 540 {
 541         struct netlbl_lsm_catmap *iter;
 542         struct netlbl_lsm_catmap *prev = NULL;
 543         u32 idx;
 544         u32 bit;
 545         NETLBL_CATMAP_MAPTYPE bitmask;
 546         NETLBL_CATMAP_MAPTYPE bitmap;
 547
 548         iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 549         if (iter == NULL)
 550                 return -ENOENT;
 551         if (offset > iter->startbit) {
 552                 offset -= iter->startbit;
 553                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 554                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 555         } else {
 556                 idx = 0;
 557                 bit = 0;
 558         }
 559         bitmask = NETLBL_CATMAP_BIT << bit;
 560
 561         for (;;) {
 562                 bitmap = iter->bitmap[idx];
 563                 while (bitmask != 0 && (bitmap & bitmask) != 0) {
 564                         bitmask <<= 1;
 565                         bit++;
 566                 }
 567
 568                 if (prev && idx == 0 && bit == 0)
 569                         return prev->startbit + NETLBL_CATMAP_SIZE - 1;
 570                 else if (bitmask != 0)
 571                         return iter->startbit +
 572                                 (NETLBL_CATMAP_MAPSIZE * idx) + bit - 1;
 573                 else if (++idx >= NETLBL_CATMAP_MAPCNT) {
 574                         if (iter->next == NULL)
 575                                 return iter->startbit + NETLBL_CATMAP_SIZE - 1;
 576                         prev = iter;
 577                         iter = iter->next;
 578                         idx = 0;
 579                 }
 580                 bitmask = NETLBL_CATMAP_BIT;
 581                 bit = 0;
 582         }
 583
 584         return -ENOENT;
 585 }
 586
 587 /**
 588  * netlbl_catmap_getlong - Export an unsigned long bitmap
 589  * @catmap: pointer to the category bitmap
 590  * @offset: pointer to the requested offset
 591  * @bitmap: the exported bitmap
 592  *
 593  * Description:
 594  * Export a bitmap with an offset greater than or equal to @offset and return
 595  * it in @bitmap.  The @offset must be aligned to an unsigned long and will be
 596  * updated on return if different from what was requested; if the catmap is
 597  * empty at the requested offset and beyond, the @offset is set to (u32)-1.
 598  * Returns zero on sucess, negative values on failure.
 599  *
 600  */
 601 int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap,
 602                           u32 *offset,
 603                           unsigned long *bitmap)
 604 {
 605         struct netlbl_lsm_catmap *iter;
 606         u32 off = *offset;
 607         u32 idx;
 608
 609         /* only allow aligned offsets */
 610         if ((off & (BITS_PER_LONG - 1)) != 0)
 611                 return -EINVAL;
 612
 613         if (off < catmap->startbit) {
 614                 off = catmap->startbit;
 615                 *offset = off;
 616         }
 617         iter = _netlbl_catmap_getnode(&catmap, off, _CM_F_WALK, 0);
 618         if (iter == NULL) {
 619                 *offset = (u32)-1;
 620                 return 0;
 621         }
 622
 623         if (off < iter->startbit) {
 624                 *offset = iter->startbit;
 625                 off = 0;
 626         } else
 627                 off -= iter->startbit;
 628         idx = off / NETLBL_CATMAP_MAPSIZE;
 629         *bitmap = iter->bitmap[idx] >> (off % NETLBL_CATMAP_MAPSIZE);
 630
 631         return 0;
 632 }
 633
 634 /**
 635  * netlbl_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_catmap_setbit(struct netlbl_lsm_catmap **catmap,
 646                          u32 bit,
 647                          gfp_t flags)
 648 {
 649         struct netlbl_lsm_catmap *iter;
 650         u32 idx;
 651
 652         iter = _netlbl_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 EXPORT_SYMBOL(netlbl_catmap_setbit);
 663
 664 /**
 665  * netlbl_catmap_setrng - Set a range of bits in a LSM secattr catmap
 666  * @catmap: pointer to the category bitmap
 667  * @start: the starting bit
 668  * @end: the last bit in the string
 669  * @flags: memory allocation flags
 670  *
 671  * Description:
 672  * Set a range of bits, starting at @start and ending with @end.  Returns zero
 673  * on success, negative values on failure.
 674  *
 675  */
 676 int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap,
 677                          u32 start,
 678                          u32 end,
 679                          gfp_t flags)
 680 {
 681         int rc = 0;
 682         u32 spot = start;
 683
 684         while (rc == 0 && spot <= end) {
 685                 if (((spot & (BITS_PER_LONG - 1)) == 0) &&
 686                     ((end - spot) > BITS_PER_LONG)) {
 687                         rc = netlbl_catmap_setlong(catmap,
 688                                                    spot,
 689                                                    (unsigned long)-1,
 690                                                    flags);
 691                         spot += BITS_PER_LONG;
 692                 } else
 693                         rc = netlbl_catmap_setbit(catmap, spot++, flags);
 694         }
 695
 696         return rc;
 697 }
 698
 699 /**
 700  * netlbl_catmap_setlong - Import an unsigned long bitmap
 701  * @catmap: pointer to the category bitmap
 702  * @offset: offset to the start of the imported bitmap
 703  * @bitmap: the bitmap to import
 704  * @flags: memory allocation flags
 705  *
 706  * Description:
 707  * Import the bitmap specified in @bitmap into @catmap, using the offset
 708  * in @offset.  The offset must be aligned to an unsigned long.  Returns zero
 709  * on success, negative values on failure.
 710  *
 711  */
 712 int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,
 713                           u32 offset,
 714                           unsigned long bitmap,
 715                           gfp_t flags)
 716 {
 717         struct netlbl_lsm_catmap *iter;
 718         u32 idx;
 719
 720         /* only allow aligned offsets */
 721         if ((offset & (BITS_PER_LONG - 1)) != 0)
 722                 return -EINVAL;
 723
 724         iter = _netlbl_catmap_getnode(catmap, offset, _CM_F_ALLOC, flags);
 725         if (iter == NULL)
 726                 return -ENOMEM;
 727
 728         offset -= iter->startbit;
 729         idx = offset / NETLBL_CATMAP_MAPSIZE;
 730         iter->bitmap[idx] |= bitmap << (offset % NETLBL_CATMAP_MAPSIZE);
 731
 732         return 0;
 733 }
 734
 735 /* Bitmap functions
 736  */
 737
 738 /**
 739  * netlbl_bitmap_walk - Walk a bitmap looking for a bit
 740  * @bitmap: the bitmap
 741  * @bitmap_len: length in bits
 742  * @offset: starting offset
 743  * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit
 744  *
 745  * Description:
 746  * Starting at @offset, walk the bitmap from left to right until either the
 747  * desired bit is found or we reach the end.  Return the bit offset, -1 if
 748  * not found, or -2 if error.
 749  */
 750 int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len,
 751                        u32 offset, u8 state)
 752 {
 753         u32 bit_spot;
 754         u32 byte_offset;
 755         unsigned char bitmask;
 756         unsigned char byte;
 757
 758         byte_offset = offset / 8;
 759         byte = bitmap[byte_offset];
 760         bit_spot = offset;
 761         bitmask = 0x80 >> (offset % 8);
 762
 763         while (bit_spot < bitmap_len) {
 764                 if ((state && (byte & bitmask) == bitmask) ||
 765                     (state == 0 && (byte & bitmask) == 0))
 766                         return bit_spot;
 767
 768                 bit_spot++;
 769                 bitmask >>= 1;
 770                 if (bitmask == 0) {
 771                         byte = bitmap[++byte_offset];
 772                         bitmask = 0x80;
 773                 }
 774         }
 775
 776         return -1;
 777 }
 778 EXPORT_SYMBOL(netlbl_bitmap_walk);
 779
 780 /**
 781  * netlbl_bitmap_setbit - Sets a single bit in a bitmap
 782  * @bitmap: the bitmap
 783  * @bit: the bit
 784  * @state: if non-zero, set the bit (1) else clear the bit (0)
 785  *
 786  * Description:
 787  * Set a single bit in the bitmask.  Returns zero on success, negative values
 788  * on error.
 789  */
 790 void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state)
 791 {
 792         u32 byte_spot;
 793         u8 bitmask;
 794
 795         /* gcc always rounds to zero when doing integer division */
 796         byte_spot = bit / 8;
 797         bitmask = 0x80 >> (bit % 8);
 798         if (state)
 799                 bitmap[byte_spot] |= bitmask;
 800         else
 801                 bitmap[byte_spot] &= ~bitmask;
 802 }
 803 EXPORT_SYMBOL(netlbl_bitmap_setbit);
 804
 805 /*
 806  * LSM Functions
 807  */
 808
 809 /**
 810  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
 811  *
 812  * Description:
 813  * The LSM can use this function to determine if it should use NetLabel
 814  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
 815  * considered to be enabled when it's configuration contains a valid setup for
 816  * at least one labeled protocol (i.e. NetLabel can understand incoming
 817  * labeled packets of at least one type); otherwise NetLabel is considered to
 818  * be disabled.
 819  *
 820  */
 821 int netlbl_enabled(void)
 822 {
 823         /* At some point we probably want to expose this mechanism to the user
 824          * as well so that admins can toggle NetLabel regardless of the
 825          * configuration */
 826         return (atomic_read(&netlabel_mgmt_protocount) > 0);
 827 }
 828
 829 /**
 830  * netlbl_sock_setattr - Label a socket using the correct protocol
 831  * @sk: the socket to label
 832  * @family: protocol family
 833  * @secattr: the security attributes
 834  *
 835  * Description:
 836  * Attach the correct label to the given socket using the security attributes
 837  * specified in @secattr.  This function requires exclusive access to @sk,
 838  * which means it either needs to be in the process of being created or locked.
 839  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
 840  * network address selectors (can't blindly label the socket), and negative
 841  * values on all other failures.
 842  *
 843  */
 844 int netlbl_sock_setattr(struct sock *sk,
 845                         u16 family,
 846                         const struct netlbl_lsm_secattr *secattr)
 847 {
 848         int ret_val;
 849         struct netlbl_dom_map *dom_entry;
 850
 851         rcu_read_lock();
 852         dom_entry = netlbl_domhsh_getentry(secattr->domain, family);
 853         if (dom_entry == NULL) {
 854                 ret_val = -ENOENT;
 855                 goto socket_setattr_return;
 856         }
 857         switch (family) {
 858         case AF_INET:
 859                 switch (dom_entry->def.type) {
 860                 case NETLBL_NLTYPE_ADDRSELECT:
 861                         ret_val = -EDESTADDRREQ;
 862                         break;
 863                 case NETLBL_NLTYPE_CIPSOV4:
 864                         ret_val = cipso_v4_sock_setattr(sk,
 865                                                         dom_entry->def.cipso,
 866                                                         secattr);
 867                         break;
 868                 case NETLBL_NLTYPE_UNLABELED:
 869                         ret_val = 0;
 870                         break;
 871                 default:
 872                         ret_val = -ENOENT;
 873                 }
 874                 break;
 875 #if IS_ENABLED(CONFIG_IPV6)
 876         case AF_INET6:
 877                 switch (dom_entry->def.type) {
 878                 case NETLBL_NLTYPE_ADDRSELECT:
 879                         ret_val = -EDESTADDRREQ;
 880                         break;
 881                 case NETLBL_NLTYPE_CALIPSO:
 882                         ret_val = calipso_sock_setattr(sk,
 883                                                        dom_entry->def.calipso,
 884                                                        secattr);
 885                         break;
 886                 case NETLBL_NLTYPE_UNLABELED:
 887                         ret_val = 0;
 888                         break;
 889                 default:
 890                         ret_val = -ENOENT;
 891                 }
 892                 break;
 893 #endif /* IPv6 */
 894         default:
 895                 ret_val = -EPROTONOSUPPORT;
 896         }
 897
 898 socket_setattr_return:
 899         rcu_read_unlock();
 900         return ret_val;
 901 }
 902
 903 /**
 904  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
 905  * @sk: the socket
 906  *
 907  * Description:
 908  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
 909  * ensuring that @sk is locked.
 910  *
 911  */
 912 void netlbl_sock_delattr(struct sock *sk)
 913 {
 914         switch (sk->sk_family) {
 915         case AF_INET:
 916                 cipso_v4_sock_delattr(sk);
 917                 break;
 918 #if IS_ENABLED(CONFIG_IPV6)
 919         case AF_INET6:
 920                 calipso_sock_delattr(sk);
 921                 break;
 922 #endif /* IPv6 */
 923         }
 924 }
 925
 926 /**
 927  * netlbl_sock_getattr - Determine the security attributes of a sock
 928  * @sk: the sock
 929  * @secattr: the security attributes
 930  *
 931  * Description:
 932  * Examines the given sock to see if any NetLabel style labeling has been
 933  * applied to the sock, if so it parses the socket label and returns the
 934  * security attributes in @secattr.  Returns zero on success, negative values
 935  * on failure.
 936  *
 937  */
 938 int netlbl_sock_getattr(struct sock *sk,
 939                         struct netlbl_lsm_secattr *secattr)
 940 {
 941         int ret_val;
 942
 943         switch (sk->sk_family) {
 944         case AF_INET:
 945                 ret_val = cipso_v4_sock_getattr(sk, secattr);
 946                 break;
 947 #if IS_ENABLED(CONFIG_IPV6)
 948         case AF_INET6:
 949                 ret_val = calipso_sock_getattr(sk, secattr);
 950                 break;
 951 #endif /* IPv6 */
 952         default:
 953                 ret_val = -EPROTONOSUPPORT;
 954         }
 955
 956         return ret_val;
 957 }
 958
 959 /**
 960  * netlbl_conn_setattr - Label a connected socket using the correct protocol
 961  * @sk: the socket to label
 962  * @addr: the destination address
 963  * @secattr: the security attributes
 964  *
 965  * Description:
 966  * Attach the correct label to the given connected socket using the security
 967  * attributes specified in @secattr.  The caller is responsible for ensuring
 968  * that @sk is locked.  Returns zero on success, negative values on failure.
 969  *
 970  */
 971 int netlbl_conn_setattr(struct sock *sk,
 972                         struct sockaddr *addr,
 973                         const struct netlbl_lsm_secattr *secattr)
 974 {
 975         int ret_val;
 976         struct sockaddr_in *addr4;
 977 #if IS_ENABLED(CONFIG_IPV6)
 978         struct sockaddr_in6 *addr6;
 979 #endif
 980         struct netlbl_dommap_def *entry;
 981
 982         rcu_read_lock();
 983         switch (addr->sa_family) {
 984         case AF_INET:
 985                 addr4 = (struct sockaddr_in *)addr;
 986                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
 987                                                    addr4->sin_addr.s_addr);
 988                 if (entry == NULL) {
 989                         ret_val = -ENOENT;
 990                         goto conn_setattr_return;
 991                 }
 992                 switch (entry->type) {
 993                 case NETLBL_NLTYPE_CIPSOV4:
 994                         ret_val = cipso_v4_sock_setattr(sk,
 995                                                         entry->cipso, secattr);
 996                         break;
 997                 case NETLBL_NLTYPE_UNLABELED:
 998                         /* just delete the protocols we support for right now
 999                          * but we could remove other protocols if needed */
1000                         netlbl_sock_delattr(sk);
1001                         ret_val = 0;
1002                         break;
1003                 default:
1004                         ret_val = -ENOENT;
1005                 }
1006                 break;
1007 #if IS_ENABLED(CONFIG_IPV6)
1008         case AF_INET6:
1009                 addr6 = (struct sockaddr_in6 *)addr;
1010                 entry = netlbl_domhsh_getentry_af6(secattr->domain,
1011                                                    &addr6->sin6_addr);
1012                 if (entry == NULL) {
1013                         ret_val = -ENOENT;
1014                         goto conn_setattr_return;
1015                 }
1016                 switch (entry->type) {
1017                 case NETLBL_NLTYPE_CALIPSO:
1018                         ret_val = calipso_sock_setattr(sk,
1019                                                        entry->calipso, secattr);
1020                         break;
1021                 case NETLBL_NLTYPE_UNLABELED:
1022                         /* just delete the protocols we support for right now
1023                          * but we could remove other protocols if needed */
1024                         netlbl_sock_delattr(sk);
1025                         ret_val = 0;
1026                         break;
1027                 default:
1028                         ret_val = -ENOENT;
1029                 }
1030                 break;
1031 #endif /* IPv6 */
1032         default:
1033                 ret_val = -EPROTONOSUPPORT;
1034         }
1035
1036 conn_setattr_return:
1037         rcu_read_unlock();
1038         return ret_val;
1039 }
1040
1041 /**
1042  * netlbl_req_setattr - Label a request socket using the correct protocol
1043  * @req: the request socket to label
1044  * @secattr: the security attributes
1045  *
1046  * Description:
1047  * Attach the correct label to the given socket using the security attributes
1048  * specified in @secattr.  Returns zero on success, negative values on failure.
1049  *
1050  */
1051 int netlbl_req_setattr(struct request_sock *req,
1052                        const struct netlbl_lsm_secattr *secattr)
1053 {
1054         int ret_val;
1055         struct netlbl_dommap_def *entry;
1056
1057         rcu_read_lock();
1058         switch (req->rsk_ops->family) {
1059         case AF_INET:
1060                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
1061                                                    inet_rsk(req)->ir_rmt_addr);
1062                 if (entry == NULL) {
1063                         ret_val = -ENOENT;
1064                         goto req_setattr_return;
1065                 }
1066                 switch (entry->type) {
1067                 case NETLBL_NLTYPE_CIPSOV4:
1068                         ret_val = cipso_v4_req_setattr(req,
1069                                                        entry->cipso, secattr);
1070                         break;
1071                 case NETLBL_NLTYPE_UNLABELED:
1072                         /* just delete the protocols we support for right now
1073                          * but we could remove other protocols if needed */
1074                         cipso_v4_req_delattr(req);
1075                         ret_val = 0;
1076                         break;
1077                 default:
1078                         ret_val = -ENOENT;
1079                 }
1080                 break;
1081 #if IS_ENABLED(CONFIG_IPV6)
1082         case AF_INET6:
1083                 /* since we don't support any IPv6 labeling protocols right
1084                  * now we can optimize everything away until we do */
1085                 ret_val = 0;
1086                 break;
1087 #endif /* IPv6 */
1088         default:
1089                 ret_val = -EPROTONOSUPPORT;
1090         }
1091
1092 req_setattr_return:
1093         rcu_read_unlock();
1094         return ret_val;
1095 }
1096
1097 /**
1098 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
1099 * @req: the socket
1100 *
1101 * Description:
1102 * Remove all the NetLabel labeling from @req.
1103 *
1104 */
1105 void netlbl_req_delattr(struct request_sock *req)
1106 {
1107         switch (req->rsk_ops->family) {
1108         case AF_INET:
1109                 cipso_v4_req_delattr(req);
1110                 break;
1111         }
1112 }
1113
1114 /**
1115  * netlbl_skbuff_setattr - Label a packet using the correct protocol
1116  * @skb: the packet
1117  * @family: protocol family
1118  * @secattr: the security attributes
1119  *
1120  * Description:
1121  * Attach the correct label to the given packet using the security attributes
1122  * specified in @secattr.  Returns zero on success, negative values on failure.
1123  *
1124  */
1125 int netlbl_skbuff_setattr(struct sk_buff *skb,
1126                           u16 family,
1127                           const struct netlbl_lsm_secattr *secattr)
1128 {
1129         int ret_val;
1130         struct iphdr *hdr4;
1131         struct netlbl_dommap_def *entry;
1132
1133         rcu_read_lock();
1134         switch (family) {
1135         case AF_INET:
1136                 hdr4 = ip_hdr(skb);
1137                 entry = netlbl_domhsh_getentry_af4(secattr->domain,hdr4->daddr);
1138                 if (entry == NULL) {
1139                         ret_val = -ENOENT;
1140                         goto skbuff_setattr_return;
1141                 }
1142                 switch (entry->type) {
1143                 case NETLBL_NLTYPE_CIPSOV4:
1144                         ret_val = cipso_v4_skbuff_setattr(skb, entry->cipso,
1145                                                           secattr);
1146                         break;
1147                 case NETLBL_NLTYPE_UNLABELED:
1148                         /* just delete the protocols we support for right now
1149                          * but we could remove other protocols if needed */
1150                         ret_val = cipso_v4_skbuff_delattr(skb);
1151                         break;
1152                 default:
1153                         ret_val = -ENOENT;
1154                 }
1155                 break;
1156 #if IS_ENABLED(CONFIG_IPV6)
1157         case AF_INET6:
1158                 /* since we don't support any IPv6 labeling protocols right
1159                  * now we can optimize everything away until we do */
1160                 ret_val = 0;
1161                 break;
1162 #endif /* IPv6 */
1163         default:
1164                 ret_val = -EPROTONOSUPPORT;
1165         }
1166
1167 skbuff_setattr_return:
1168         rcu_read_unlock();
1169         return ret_val;
1170 }
1171
1172 /**
1173  * netlbl_skbuff_getattr - Determine the security attributes of a packet
1174  * @skb: the packet
1175  * @family: protocol family
1176  * @secattr: the security attributes
1177  *
1178  * Description:
1179  * Examines the given packet to see if a recognized form of packet labeling
1180  * is present, if so it parses the packet label and returns the security
1181  * attributes in @secattr.  Returns zero on success, negative values on
1182  * failure.
1183  *
1184  */
1185 int netlbl_skbuff_getattr(const struct sk_buff *skb,
1186                           u16 family,
1187                           struct netlbl_lsm_secattr *secattr)
1188 {
1189         unsigned char *ptr;
1190
1191         switch (family) {
1192         case AF_INET:
1193                 ptr = cipso_v4_optptr(skb);
1194                 if (ptr && cipso_v4_getattr(ptr, secattr) == 0)
1195                         return 0;
1196                 break;
1197 #if IS_ENABLED(CONFIG_IPV6)
1198         case AF_INET6:
1199                 break;
1200 #endif /* IPv6 */
1201         }
1202
1203         return netlbl_unlabel_getattr(skb, family, secattr);
1204 }
1205
1206 /**
1207  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
1208  * @skb: the packet
1209  * @error: the error code
1210  * @gateway: true if host is acting as a gateway, false otherwise
1211  *
1212  * Description:
1213  * Deal with a LSM problem when handling the packet in @skb, typically this is
1214  * a permission denied problem (-EACCES).  The correct action is determined
1215  * according to the packet's labeling protocol.
1216  *
1217  */
1218 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
1219 {
1220         if (cipso_v4_optptr(skb))
1221                 cipso_v4_error(skb, error, gateway);
1222 }
1223
1224 /**
1225  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
1226  *
1227  * Description:
1228  * For all of the NetLabel protocols that support some form of label mapping
1229  * cache, invalidate the cache.  Returns zero on success, negative values on
1230  * error.
1231  *
1232  */
1233 void netlbl_cache_invalidate(void)
1234 {
1235         cipso_v4_cache_invalidate();
1236 }
1237
1238 /**
1239  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1240  * @skb: the packet
1241  * @secattr: the packet's security attributes
1242  *
1243  * Description:
1244  * Add the LSM security attributes for the given packet to the underlying
1245  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1246  * values on error.
1247  *
1248  */
1249 int netlbl_cache_add(const struct sk_buff *skb,
1250                      const struct netlbl_lsm_secattr *secattr)
1251 {
1252         unsigned char *ptr;
1253
1254         if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1255                 return -ENOMSG;
1256
1257         ptr = cipso_v4_optptr(skb);
1258         if (ptr)
1259                 return cipso_v4_cache_add(ptr, secattr);
1260
1261         return -ENOMSG;
1262 }
1263
1264 /*
1265  * Protocol Engine Functions
1266  */
1267
1268 /**
1269  * netlbl_audit_start - Start an audit message
1270  * @type: audit message type
1271  * @audit_info: NetLabel audit information
1272  *
1273  * Description:
1274  * Start an audit message using the type specified in @type and fill the audit
1275  * message with some fields common to all NetLabel audit messages.  This
1276  * function should only be used by protocol engines, not LSMs.  Returns a
1277  * pointer to the audit buffer on success, NULL on failure.
1278  *
1279  */
1280 struct audit_buffer *netlbl_audit_start(int type,
1281                                         struct netlbl_audit *audit_info)
1282 {
1283         return netlbl_audit_start_common(type, audit_info);
1284 }
1285 EXPORT_SYMBOL(netlbl_audit_start);
1286
1287 /*
1288  * Setup Functions
1289  */
1290
1291 /**
1292  * netlbl_init - Initialize NetLabel
1293  *
1294  * Description:
1295  * Perform the required NetLabel initialization before first use.
1296  *
1297  */
1298 static int __init netlbl_init(void)
1299 {
1300         int ret_val;
1301
1302         printk(KERN_INFO "NetLabel: Initializing\n");
1303         printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1304                (1 << NETLBL_DOMHSH_BITSIZE));
1305         printk(KERN_INFO "NetLabel:  protocols ="
1306                " UNLABELED"
1307                " CIPSOv4"
1308                "\n");
1309
1310         ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1311         if (ret_val != 0)
1312                 goto init_failure;
1313
1314         ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1315         if (ret_val != 0)
1316                 goto init_failure;
1317
1318         ret_val = netlbl_netlink_init();
1319         if (ret_val != 0)
1320                 goto init_failure;
1321
1322         ret_val = netlbl_unlabel_defconf();
1323         if (ret_val != 0)
1324                 goto init_failure;
1325         printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1326
1327         return 0;
1328
1329 init_failure:
1330         panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1331 }
1332
1333 subsys_initcall(netlbl_init);