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, family, 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         entry->family = family;
 123
 124         if (addr == NULL && mask == NULL)
 125                 entry->def.type = NETLBL_NLTYPE_UNLABELED;
 126         else if (addr != NULL && mask != NULL) {
 127                 addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
 128                 if (addrmap == NULL)
 129                         goto cfg_unlbl_map_add_failure;
 130                 INIT_LIST_HEAD(&addrmap->list4);
 131                 INIT_LIST_HEAD(&addrmap->list6);
 132
 133                 switch (family) {
 134                 case AF_INET: {
 135                         const struct in_addr *addr4 = addr;
 136                         const struct in_addr *mask4 = mask;
 137                         map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
 138                         if (map4 == NULL)
 139                                 goto cfg_unlbl_map_add_failure;
 140                         map4->def.type = NETLBL_NLTYPE_UNLABELED;
 141                         map4->list.addr = addr4->s_addr & mask4->s_addr;
 142                         map4->list.mask = mask4->s_addr;
 143                         map4->list.valid = 1;
 144                         ret_val = netlbl_af4list_add(&map4->list,
 145                                                      &addrmap->list4);
 146                         if (ret_val != 0)
 147                                 goto cfg_unlbl_map_add_failure;
 148                         break;
 149                         }
 150 #if IS_ENABLED(CONFIG_IPV6)
 151                 case AF_INET6: {
 152                         const struct in6_addr *addr6 = addr;
 153                         const struct in6_addr *mask6 = mask;
 154                         map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
 155                         if (map6 == NULL)
 156                                 goto cfg_unlbl_map_add_failure;
 157                         map6->def.type = NETLBL_NLTYPE_UNLABELED;
 158                         map6->list.addr = *addr6;
 159                         map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
 160                         map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
 161                         map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
 162                         map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
 163                         map6->list.mask = *mask6;
 164                         map6->list.valid = 1;
 165                         ret_val = netlbl_af6list_add(&map6->list,
 166                                                      &addrmap->list6);
 167                         if (ret_val != 0)
 168                                 goto cfg_unlbl_map_add_failure;
 169                         break;
 170                         }
 171 #endif /* IPv6 */
 172                 default:
 173                         goto cfg_unlbl_map_add_failure;
 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  * @audit_info: NetLabel audit information
 251  *
 252  * Description:
 253  * Removes an existing NetLabel static label used when protocol provided labels
 254  * are not present on incoming traffic.  If @dev_name is NULL then the default
 255  * interface will be used.  Returns zero on success, negative values on failure.
 256  *
 257  */
 258 int netlbl_cfg_unlbl_static_del(struct net *net,
 259                                 const char *dev_name,
 260                                 const void *addr,
 261                                 const void *mask,
 262                                 u16 family,
 263                                 struct netlbl_audit *audit_info)
 264 {
 265         u32 addr_len;
 266
 267         switch (family) {
 268         case AF_INET:
 269                 addr_len = sizeof(struct in_addr);
 270                 break;
 271 #if IS_ENABLED(CONFIG_IPV6)
 272         case AF_INET6:
 273                 addr_len = sizeof(struct in6_addr);
 274                 break;
 275 #endif /* IPv6 */
 276         default:
 277                 return -EPFNOSUPPORT;
 278         }
 279
 280         return netlbl_unlhsh_remove(net,
 281                                     dev_name, addr, mask, addr_len,
 282                                     audit_info);
 283 }
 284
 285 /**
 286  * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition
 287  * @doi_def: CIPSO DOI definition
 288  * @audit_info: NetLabel audit information
 289  *
 290  * Description:
 291  * Add a new CIPSO DOI definition as defined by @doi_def.  Returns zero on
 292  * success and negative values on failure.
 293  *
 294  */
 295 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
 296                            struct netlbl_audit *audit_info)
 297 {
 298         return cipso_v4_doi_add(doi_def, audit_info);
 299 }
 300
 301 /**
 302  * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition
 303  * @doi: CIPSO DOI
 304  * @audit_info: NetLabel audit information
 305  *
 306  * Description:
 307  * Remove an existing CIPSO DOI definition matching @doi.  Returns zero on
 308  * success and negative values on failure.
 309  *
 310  */
 311 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info)
 312 {
 313         cipso_v4_doi_remove(doi, audit_info);
 314 }
 315
 316 /**
 317  * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping
 318  * @doi: the CIPSO DOI
 319  * @domain: the domain mapping to add
 320  * @addr: IP address
 321  * @mask: IP address mask
 322  * @audit_info: NetLabel audit information
 323  *
 324  * Description:
 325  * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel
 326  * subsystem.  A @domain value of NULL adds a new default domain mapping.
 327  * Returns zero on success, negative values on failure.
 328  *
 329  */
 330 int netlbl_cfg_cipsov4_map_add(u32 doi,
 331                                const char *domain,
 332                                const struct in_addr *addr,
 333                                const struct in_addr *mask,
 334                                struct netlbl_audit *audit_info)
 335 {
 336         int ret_val = -ENOMEM;
 337         struct cipso_v4_doi *doi_def;
 338         struct netlbl_dom_map *entry;
 339         struct netlbl_domaddr_map *addrmap = NULL;
 340         struct netlbl_domaddr4_map *addrinfo = NULL;
 341
 342         doi_def = cipso_v4_doi_getdef(doi);
 343         if (doi_def == NULL)
 344                 return -ENOENT;
 345
 346         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 347         if (entry == NULL)
 348                 goto out_entry;
 349         entry->family = AF_INET;
 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_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_catmap *_netlbl_catmap_getnode(
 428                                              struct netlbl_lsm_catmap **catmap,
 429                                              u32 offset,
 430                                              unsigned int cm_flags,
 431                                              gfp_t gfp_flags)
 432 {
 433         struct netlbl_lsm_catmap *iter = *catmap;
 434         struct netlbl_lsm_catmap *prev = NULL;
 435
 436         if (iter == NULL)
 437                 goto catmap_getnode_alloc;
 438         if (offset < iter->startbit)
 439                 goto 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 catmap_getnode_walk;
 446
 447         return iter;
 448
 449 catmap_getnode_walk:
 450         if (cm_flags & _CM_F_WALK)
 451                 return iter;
 452 catmap_getnode_alloc:
 453         if (!(cm_flags & _CM_F_ALLOC))
 454                 return NULL;
 455
 456         iter = netlbl_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_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_catmap_walk(struct netlbl_lsm_catmap *catmap, u32 offset)
 483 {
 484         struct netlbl_lsm_catmap *iter = catmap;
 485         u32 idx;
 486         u32 bit;
 487         NETLBL_CATMAP_MAPTYPE bitmap;
 488
 489         iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 490         if (iter == NULL)
 491                 return -ENOENT;
 492         if (offset > iter->startbit) {
 493                 offset -= iter->startbit;
 494                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 495                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 496         } else {
 497                 idx = 0;
 498                 bit = 0;
 499         }
 500         bitmap = iter->bitmap[idx] >> bit;
 501
 502         for (;;) {
 503                 if (bitmap != 0) {
 504                         while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
 505                                 bitmap >>= 1;
 506                                 bit++;
 507                         }
 508                         return iter->startbit +
 509                                (NETLBL_CATMAP_MAPSIZE * idx) + bit;
 510                 }
 511                 if (++idx >= NETLBL_CATMAP_MAPCNT) {
 512                         if (iter->next != NULL) {
 513                                 iter = iter->next;
 514                                 idx = 0;
 515                         } else
 516                                 return -ENOENT;
 517                 }
 518                 bitmap = iter->bitmap[idx];
 519                 bit = 0;
 520         }
 521
 522         return -ENOENT;
 523 }
 524
 525 /**
 526  * netlbl_catmap_walkrng - Find the end of a string of set bits
 527  * @catmap: the category bitmap
 528  * @offset: the offset to start searching at, in bits
 529  *
 530  * Description:
 531  * This function walks a LSM secattr category bitmap starting at @offset and
 532  * returns the spot of the first cleared bit or -ENOENT if the offset is past
 533  * the end of the bitmap.
 534  *
 535  */
 536 int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap, u32 offset)
 537 {
 538         struct netlbl_lsm_catmap *iter;
 539         struct netlbl_lsm_catmap *prev = NULL;
 540         u32 idx;
 541         u32 bit;
 542         NETLBL_CATMAP_MAPTYPE bitmask;
 543         NETLBL_CATMAP_MAPTYPE bitmap;
 544
 545         iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
 546         if (iter == NULL)
 547                 return -ENOENT;
 548         if (offset > iter->startbit) {
 549                 offset -= iter->startbit;
 550                 idx = offset / NETLBL_CATMAP_MAPSIZE;
 551                 bit = offset % NETLBL_CATMAP_MAPSIZE;
 552         } else {
 553                 idx = 0;
 554                 bit = 0;
 555         }
 556         bitmask = NETLBL_CATMAP_BIT << bit;
 557
 558         for (;;) {
 559                 bitmap = iter->bitmap[idx];
 560                 while (bitmask != 0 && (bitmap & bitmask) != 0) {
 561                         bitmask <<= 1;
 562                         bit++;
 563                 }
 564
 565                 if (prev && idx == 0 && bit == 0)
 566                         return prev->startbit + NETLBL_CATMAP_SIZE - 1;
 567                 else if (bitmask != 0)
 568                         return iter->startbit +
 569                                 (NETLBL_CATMAP_MAPSIZE * idx) + bit - 1;
 570                 else if (++idx >= NETLBL_CATMAP_MAPCNT) {
 571                         if (iter->next == NULL)
 572                                 return iter->startbit + NETLBL_CATMAP_SIZE - 1;
 573                         prev = iter;
 574                         iter = iter->next;
 575                         idx = 0;
 576                 }
 577                 bitmask = NETLBL_CATMAP_BIT;
 578                 bit = 0;
 579         }
 580
 581         return -ENOENT;
 582 }
 583
 584 /**
 585  * netlbl_catmap_getlong - Export an unsigned long bitmap
 586  * @catmap: pointer to the category bitmap
 587  * @offset: pointer to the requested offset
 588  * @bitmap: the exported bitmap
 589  *
 590  * Description:
 591  * Export a bitmap with an offset greater than or equal to @offset and return
 592  * it in @bitmap.  The @offset must be aligned to an unsigned long and will be
 593  * updated on return if different from what was requested; if the catmap is
 594  * empty at the requested offset and beyond, the @offset is set to (u32)-1.
 595  * Returns zero on sucess, negative values on failure.
 596  *
 597  */
 598 int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap,
 599                           u32 *offset,
 600                           unsigned long *bitmap)
 601 {
 602         struct netlbl_lsm_catmap *iter;
 603         u32 off = *offset;
 604         u32 idx;
 605
 606         /* only allow aligned offsets */
 607         if ((off & (BITS_PER_LONG - 1)) != 0)
 608                 return -EINVAL;
 609
 610         if (off < catmap->startbit) {
 611                 off = catmap->startbit;
 612                 *offset = off;
 613         }
 614         iter = _netlbl_catmap_getnode(&catmap, off, _CM_F_WALK, 0);
 615         if (iter == NULL) {
 616                 *offset = (u32)-1;
 617                 return 0;
 618         }
 619
 620         if (off < iter->startbit) {
 621                 *offset = iter->startbit;
 622                 off = 0;
 623         } else
 624                 off -= iter->startbit;
 625         idx = off / NETLBL_CATMAP_MAPSIZE;
 626         *bitmap = iter->bitmap[idx] >> (off % NETLBL_CATMAP_MAPSIZE);
 627
 628         return 0;
 629 }
 630
 631 /**
 632  * netlbl_catmap_setbit - Set a bit in a LSM secattr catmap
 633  * @catmap: pointer to the category bitmap
 634  * @bit: the bit to set
 635  * @flags: memory allocation flags
 636  *
 637  * Description:
 638  * Set the bit specified by @bit in @catmap.  Returns zero on success,
 639  * negative values on failure.
 640  *
 641  */
 642 int netlbl_catmap_setbit(struct netlbl_lsm_catmap **catmap,
 643                          u32 bit,
 644                          gfp_t flags)
 645 {
 646         struct netlbl_lsm_catmap *iter;
 647         u32 idx;
 648
 649         iter = _netlbl_catmap_getnode(catmap, bit, _CM_F_ALLOC, flags);
 650         if (iter == NULL)
 651                 return -ENOMEM;
 652
 653         bit -= iter->startbit;
 654         idx = bit / NETLBL_CATMAP_MAPSIZE;
 655         iter->bitmap[idx] |= NETLBL_CATMAP_BIT << (bit % NETLBL_CATMAP_MAPSIZE);
 656
 657         return 0;
 658 }
 659
 660 /**
 661  * netlbl_catmap_setrng - Set a range of bits in a LSM secattr catmap
 662  * @catmap: pointer to the category bitmap
 663  * @start: the starting bit
 664  * @end: the last bit in the string
 665  * @flags: memory allocation flags
 666  *
 667  * Description:
 668  * Set a range of bits, starting at @start and ending with @end.  Returns zero
 669  * on success, negative values on failure.
 670  *
 671  */
 672 int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap,
 673                          u32 start,
 674                          u32 end,
 675                          gfp_t flags)
 676 {
 677         int rc = 0;
 678         u32 spot = start;
 679
 680         while (rc == 0 && spot <= end) {
 681                 if (((spot & (BITS_PER_LONG - 1)) == 0) &&
 682                     ((end - spot) > BITS_PER_LONG)) {
 683                         rc = netlbl_catmap_setlong(catmap,
 684                                                    spot,
 685                                                    (unsigned long)-1,
 686                                                    flags);
 687                         spot += BITS_PER_LONG;
 688                 } else
 689                         rc = netlbl_catmap_setbit(catmap, spot++, flags);
 690         }
 691
 692         return rc;
 693 }
 694
 695 /**
 696  * netlbl_catmap_setlong - Import an unsigned long bitmap
 697  * @catmap: pointer to the category bitmap
 698  * @offset: offset to the start of the imported bitmap
 699  * @bitmap: the bitmap to import
 700  * @flags: memory allocation flags
 701  *
 702  * Description:
 703  * Import the bitmap specified in @bitmap into @catmap, using the offset
 704  * in @offset.  The offset must be aligned to an unsigned long.  Returns zero
 705  * on success, negative values on failure.
 706  *
 707  */
 708 int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,
 709                           u32 offset,
 710                           unsigned long bitmap,
 711                           gfp_t flags)
 712 {
 713         struct netlbl_lsm_catmap *iter;
 714         u32 idx;
 715
 716         /* only allow aligned offsets */
 717         if ((offset & (BITS_PER_LONG - 1)) != 0)
 718                 return -EINVAL;
 719
 720         iter = _netlbl_catmap_getnode(catmap, offset, _CM_F_ALLOC, flags);
 721         if (iter == NULL)
 722                 return -ENOMEM;
 723
 724         offset -= iter->startbit;
 725         idx = offset / NETLBL_CATMAP_MAPSIZE;
 726         iter->bitmap[idx] |= bitmap << (offset % NETLBL_CATMAP_MAPSIZE);
 727
 728         return 0;
 729 }
 730
 731 /*
 732  * LSM Functions
 733  */
 734
 735 /**
 736  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
 737  *
 738  * Description:
 739  * The LSM can use this function to determine if it should use NetLabel
 740  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
 741  * considered to be enabled when it's configuration contains a valid setup for
 742  * at least one labeled protocol (i.e. NetLabel can understand incoming
 743  * labeled packets of at least one type); otherwise NetLabel is considered to
 744  * be disabled.
 745  *
 746  */
 747 int netlbl_enabled(void)
 748 {
 749         /* At some point we probably want to expose this mechanism to the user
 750          * as well so that admins can toggle NetLabel regardless of the
 751          * configuration */
 752         return (atomic_read(&netlabel_mgmt_protocount) > 0);
 753 }
 754
 755 /**
 756  * netlbl_sock_setattr - Label a socket using the correct protocol
 757  * @sk: the socket to label
 758  * @family: protocol family
 759  * @secattr: the security attributes
 760  *
 761  * Description:
 762  * Attach the correct label to the given socket using the security attributes
 763  * specified in @secattr.  This function requires exclusive access to @sk,
 764  * which means it either needs to be in the process of being created or locked.
 765  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
 766  * network address selectors (can't blindly label the socket), and negative
 767  * values on all other failures.
 768  *
 769  */
 770 int netlbl_sock_setattr(struct sock *sk,
 771                         u16 family,
 772                         const struct netlbl_lsm_secattr *secattr)
 773 {
 774         int ret_val;
 775         struct netlbl_dom_map *dom_entry;
 776
 777         rcu_read_lock();
 778         dom_entry = netlbl_domhsh_getentry(secattr->domain, family);
 779         if (dom_entry == NULL) {
 780                 ret_val = -ENOENT;
 781                 goto socket_setattr_return;
 782         }
 783         switch (family) {
 784         case AF_INET:
 785                 switch (dom_entry->def.type) {
 786                 case NETLBL_NLTYPE_ADDRSELECT:
 787                         ret_val = -EDESTADDRREQ;
 788                         break;
 789                 case NETLBL_NLTYPE_CIPSOV4:
 790                         ret_val = cipso_v4_sock_setattr(sk,
 791                                                         dom_entry->def.cipso,
 792                                                         secattr);
 793                         break;
 794                 case NETLBL_NLTYPE_UNLABELED:
 795                         ret_val = 0;
 796                         break;
 797                 default:
 798                         ret_val = -ENOENT;
 799                 }
 800                 break;
 801 #if IS_ENABLED(CONFIG_IPV6)
 802         case AF_INET6:
 803                 /* since we don't support any IPv6 labeling protocols right
 804                  * now we can optimize everything away until we do */
 805                 ret_val = 0;
 806                 break;
 807 #endif /* IPv6 */
 808         default:
 809                 ret_val = -EPROTONOSUPPORT;
 810         }
 811
 812 socket_setattr_return:
 813         rcu_read_unlock();
 814         return ret_val;
 815 }
 816
 817 /**
 818  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
 819  * @sk: the socket
 820  *
 821  * Description:
 822  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
 823  * ensuring that @sk is locked.
 824  *
 825  */
 826 void netlbl_sock_delattr(struct sock *sk)
 827 {
 828         switch (sk->sk_family) {
 829         case AF_INET:
 830                 cipso_v4_sock_delattr(sk);
 831                 break;
 832         }
 833 }
 834
 835 /**
 836  * netlbl_sock_getattr - Determine the security attributes of a sock
 837  * @sk: the sock
 838  * @secattr: the security attributes
 839  *
 840  * Description:
 841  * Examines the given sock to see if any NetLabel style labeling has been
 842  * applied to the sock, if so it parses the socket label and returns the
 843  * security attributes in @secattr.  Returns zero on success, negative values
 844  * on failure.
 845  *
 846  */
 847 int netlbl_sock_getattr(struct sock *sk,
 848                         struct netlbl_lsm_secattr *secattr)
 849 {
 850         int ret_val;
 851
 852         switch (sk->sk_family) {
 853         case AF_INET:
 854                 ret_val = cipso_v4_sock_getattr(sk, secattr);
 855                 break;
 856 #if IS_ENABLED(CONFIG_IPV6)
 857         case AF_INET6:
 858                 ret_val = -ENOMSG;
 859                 break;
 860 #endif /* IPv6 */
 861         default:
 862                 ret_val = -EPROTONOSUPPORT;
 863         }
 864
 865         return ret_val;
 866 }
 867
 868 /**
 869  * netlbl_conn_setattr - Label a connected socket using the correct protocol
 870  * @sk: the socket to label
 871  * @addr: the destination address
 872  * @secattr: the security attributes
 873  *
 874  * Description:
 875  * Attach the correct label to the given connected socket using the security
 876  * attributes specified in @secattr.  The caller is responsible for ensuring
 877  * that @sk is locked.  Returns zero on success, negative values on failure.
 878  *
 879  */
 880 int netlbl_conn_setattr(struct sock *sk,
 881                         struct sockaddr *addr,
 882                         const struct netlbl_lsm_secattr *secattr)
 883 {
 884         int ret_val;
 885         struct sockaddr_in *addr4;
 886         struct netlbl_dommap_def *entry;
 887
 888         rcu_read_lock();
 889         switch (addr->sa_family) {
 890         case AF_INET:
 891                 addr4 = (struct sockaddr_in *)addr;
 892                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
 893                                                    addr4->sin_addr.s_addr);
 894                 if (entry == NULL) {
 895                         ret_val = -ENOENT;
 896                         goto conn_setattr_return;
 897                 }
 898                 switch (entry->type) {
 899                 case NETLBL_NLTYPE_CIPSOV4:
 900                         ret_val = cipso_v4_sock_setattr(sk,
 901                                                         entry->cipso, secattr);
 902                         break;
 903                 case NETLBL_NLTYPE_UNLABELED:
 904                         /* just delete the protocols we support for right now
 905                          * but we could remove other protocols if needed */
 906                         cipso_v4_sock_delattr(sk);
 907                         ret_val = 0;
 908                         break;
 909                 default:
 910                         ret_val = -ENOENT;
 911                 }
 912                 break;
 913 #if IS_ENABLED(CONFIG_IPV6)
 914         case AF_INET6:
 915                 /* since we don't support any IPv6 labeling protocols right
 916                  * now we can optimize everything away until we do */
 917                 ret_val = 0;
 918                 break;
 919 #endif /* IPv6 */
 920         default:
 921                 ret_val = -EPROTONOSUPPORT;
 922         }
 923
 924 conn_setattr_return:
 925         rcu_read_unlock();
 926         return ret_val;
 927 }
 928
 929 /**
 930  * netlbl_req_setattr - Label a request socket using the correct protocol
 931  * @req: the request socket to label
 932  * @secattr: the security attributes
 933  *
 934  * Description:
 935  * Attach the correct label to the given socket using the security attributes
 936  * specified in @secattr.  Returns zero on success, negative values on failure.
 937  *
 938  */
 939 int netlbl_req_setattr(struct request_sock *req,
 940                        const struct netlbl_lsm_secattr *secattr)
 941 {
 942         int ret_val;
 943         struct netlbl_dommap_def *entry;
 944
 945         rcu_read_lock();
 946         switch (req->rsk_ops->family) {
 947         case AF_INET:
 948                 entry = netlbl_domhsh_getentry_af4(secattr->domain,
 949                                                    inet_rsk(req)->ir_rmt_addr);
 950                 if (entry == NULL) {
 951                         ret_val = -ENOENT;
 952                         goto req_setattr_return;
 953                 }
 954                 switch (entry->type) {
 955                 case NETLBL_NLTYPE_CIPSOV4:
 956                         ret_val = cipso_v4_req_setattr(req,
 957                                                        entry->cipso, secattr);
 958                         break;
 959                 case NETLBL_NLTYPE_UNLABELED:
 960                         /* just delete the protocols we support for right now
 961                          * but we could remove other protocols if needed */
 962                         cipso_v4_req_delattr(req);
 963                         ret_val = 0;
 964                         break;
 965                 default:
 966                         ret_val = -ENOENT;
 967                 }
 968                 break;
 969 #if IS_ENABLED(CONFIG_IPV6)
 970         case AF_INET6:
 971                 /* since we don't support any IPv6 labeling protocols right
 972                  * now we can optimize everything away until we do */
 973                 ret_val = 0;
 974                 break;
 975 #endif /* IPv6 */
 976         default:
 977                 ret_val = -EPROTONOSUPPORT;
 978         }
 979
 980 req_setattr_return:
 981         rcu_read_unlock();
 982         return ret_val;
 983 }
 984
 985 /**
 986 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
 987 * @req: the socket
 988 *
 989 * Description:
 990 * Remove all the NetLabel labeling from @req.
 991 *
 992 */
 993 void netlbl_req_delattr(struct request_sock *req)
 994 {
 995         switch (req->rsk_ops->family) {
 996         case AF_INET:
 997                 cipso_v4_req_delattr(req);
 998                 break;
 999         }
1000 }
1001
1002 /**
1003  * netlbl_skbuff_setattr - Label a packet using the correct protocol
1004  * @skb: the packet
1005  * @family: protocol family
1006  * @secattr: the security attributes
1007  *
1008  * Description:
1009  * Attach the correct label to the given packet using the security attributes
1010  * specified in @secattr.  Returns zero on success, negative values on failure.
1011  *
1012  */
1013 int netlbl_skbuff_setattr(struct sk_buff *skb,
1014                           u16 family,
1015                           const struct netlbl_lsm_secattr *secattr)
1016 {
1017         int ret_val;
1018         struct iphdr *hdr4;
1019         struct netlbl_dommap_def *entry;
1020
1021         rcu_read_lock();
1022         switch (family) {
1023         case AF_INET:
1024                 hdr4 = ip_hdr(skb);
1025                 entry = netlbl_domhsh_getentry_af4(secattr->domain,hdr4->daddr);
1026                 if (entry == NULL) {
1027                         ret_val = -ENOENT;
1028                         goto skbuff_setattr_return;
1029                 }
1030                 switch (entry->type) {
1031                 case NETLBL_NLTYPE_CIPSOV4:
1032                         ret_val = cipso_v4_skbuff_setattr(skb, entry->cipso,
1033                                                           secattr);
1034                         break;
1035                 case NETLBL_NLTYPE_UNLABELED:
1036                         /* just delete the protocols we support for right now
1037                          * but we could remove other protocols if needed */
1038                         ret_val = cipso_v4_skbuff_delattr(skb);
1039                         break;
1040                 default:
1041                         ret_val = -ENOENT;
1042                 }
1043                 break;
1044 #if IS_ENABLED(CONFIG_IPV6)
1045         case AF_INET6:
1046                 /* since we don't support any IPv6 labeling protocols right
1047                  * now we can optimize everything away until we do */
1048                 ret_val = 0;
1049                 break;
1050 #endif /* IPv6 */
1051         default:
1052                 ret_val = -EPROTONOSUPPORT;
1053         }
1054
1055 skbuff_setattr_return:
1056         rcu_read_unlock();
1057         return ret_val;
1058 }
1059
1060 /**
1061  * netlbl_skbuff_getattr - Determine the security attributes of a packet
1062  * @skb: the packet
1063  * @family: protocol family
1064  * @secattr: the security attributes
1065  *
1066  * Description:
1067  * Examines the given packet to see if a recognized form of packet labeling
1068  * is present, if so it parses the packet label and returns the security
1069  * attributes in @secattr.  Returns zero on success, negative values on
1070  * failure.
1071  *
1072  */
1073 int netlbl_skbuff_getattr(const struct sk_buff *skb,
1074                           u16 family,
1075                           struct netlbl_lsm_secattr *secattr)
1076 {
1077         unsigned char *ptr;
1078
1079         switch (family) {
1080         case AF_INET:
1081                 ptr = cipso_v4_optptr(skb);
1082                 if (ptr && cipso_v4_getattr(ptr, secattr) == 0)
1083                         return 0;
1084                 break;
1085 #if IS_ENABLED(CONFIG_IPV6)
1086         case AF_INET6:
1087                 break;
1088 #endif /* IPv6 */
1089         }
1090
1091         return netlbl_unlabel_getattr(skb, family, secattr);
1092 }
1093
1094 /**
1095  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
1096  * @skb: the packet
1097  * @error: the error code
1098  * @gateway: true if host is acting as a gateway, false otherwise
1099  *
1100  * Description:
1101  * Deal with a LSM problem when handling the packet in @skb, typically this is
1102  * a permission denied problem (-EACCES).  The correct action is determined
1103  * according to the packet's labeling protocol.
1104  *
1105  */
1106 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
1107 {
1108         if (cipso_v4_optptr(skb))
1109                 cipso_v4_error(skb, error, gateway);
1110 }
1111
1112 /**
1113  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
1114  *
1115  * Description:
1116  * For all of the NetLabel protocols that support some form of label mapping
1117  * cache, invalidate the cache.  Returns zero on success, negative values on
1118  * error.
1119  *
1120  */
1121 void netlbl_cache_invalidate(void)
1122 {
1123         cipso_v4_cache_invalidate();
1124 }
1125
1126 /**
1127  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1128  * @skb: the packet
1129  * @secattr: the packet's security attributes
1130  *
1131  * Description:
1132  * Add the LSM security attributes for the given packet to the underlying
1133  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1134  * values on error.
1135  *
1136  */
1137 int netlbl_cache_add(const struct sk_buff *skb,
1138                      const struct netlbl_lsm_secattr *secattr)
1139 {
1140         unsigned char *ptr;
1141
1142         if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1143                 return -ENOMSG;
1144
1145         ptr = cipso_v4_optptr(skb);
1146         if (ptr)
1147                 return cipso_v4_cache_add(ptr, secattr);
1148
1149         return -ENOMSG;
1150 }
1151
1152 /*
1153  * Protocol Engine Functions
1154  */
1155
1156 /**
1157  * netlbl_audit_start - Start an audit message
1158  * @type: audit message type
1159  * @audit_info: NetLabel audit information
1160  *
1161  * Description:
1162  * Start an audit message using the type specified in @type and fill the audit
1163  * message with some fields common to all NetLabel audit messages.  This
1164  * function should only be used by protocol engines, not LSMs.  Returns a
1165  * pointer to the audit buffer on success, NULL on failure.
1166  *
1167  */
1168 struct audit_buffer *netlbl_audit_start(int type,
1169                                         struct netlbl_audit *audit_info)
1170 {
1171         return netlbl_audit_start_common(type, audit_info);
1172 }
1173 EXPORT_SYMBOL(netlbl_audit_start);
1174
1175 /*
1176  * Setup Functions
1177  */
1178
1179 /**
1180  * netlbl_init - Initialize NetLabel
1181  *
1182  * Description:
1183  * Perform the required NetLabel initialization before first use.
1184  *
1185  */
1186 static int __init netlbl_init(void)
1187 {
1188         int ret_val;
1189
1190         printk(KERN_INFO "NetLabel: Initializing\n");
1191         printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1192                (1 << NETLBL_DOMHSH_BITSIZE));
1193         printk(KERN_INFO "NetLabel:  protocols ="
1194                " UNLABELED"
1195                " CIPSOv4"
1196                "\n");
1197
1198         ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1199         if (ret_val != 0)
1200                 goto init_failure;
1201
1202         ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1203         if (ret_val != 0)
1204                 goto init_failure;
1205
1206         ret_val = netlbl_netlink_init();
1207         if (ret_val != 0)
1208                 goto init_failure;
1209
1210         ret_val = netlbl_unlabel_defconf();
1211         if (ret_val != 0)
1212                 goto init_failure;
1213         printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1214
1215         return 0;
1216
1217 init_failure:
1218         panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1219 }
1220
1221 subsys_initcall(netlbl_init);