1 /* 2 * NetLabel Domain Hash Table 3 * 4 * This file manages the domain hash table that NetLabel uses to determine 5 * which network labeling protocol to use for a given domain. The NetLabel 6 * system manages static and dynamic label mappings for network protocols such 7 * as CIPSO and RIPSO. 8 * 9 * Author: Paul Moore <paul.moore@hp.com> 10 * 11 */ 12 13 /* 14 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License as published by 18 * the Free Software Foundation; either version 2 of the License, or 19 * (at your option) any later version. 20 * 21 * This program is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 24 * the GNU General Public License for more details. 25 * 26 * You should have received a copy of the GNU General Public License 27 * along with this program; if not, write to the Free Software 28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 29 * 30 */ 31 32 #include <linux/types.h> 33 #include <linux/rculist.h> 34 #include <linux/skbuff.h> 35 #include <linux/spinlock.h> 36 #include <linux/string.h> 37 #include <linux/audit.h> 38 #include <net/netlabel.h> 39 #include <net/cipso_ipv4.h> 40 #include <asm/bug.h> 41 42 #include "netlabel_mgmt.h" 43 #include "netlabel_addrlist.h" 44 #include "netlabel_domainhash.h" 45 #include "netlabel_user.h" 46 47 struct netlbl_domhsh_tbl { 48 struct list_head *tbl; 49 u32 size; 50 }; 51 52 /* Domain hash table */ 53 /* XXX - updates should be so rare that having one spinlock for the entire 54 * hash table should be okay */ 55 static DEFINE_SPINLOCK(netlbl_domhsh_lock); 56 static struct netlbl_domhsh_tbl *netlbl_domhsh = NULL; 57 static struct netlbl_dom_map *netlbl_domhsh_def = NULL; 58 59 /* 60 * Domain Hash Table Helper Functions 61 */ 62 63 /** 64 * netlbl_domhsh_free_entry - Frees a domain hash table entry 65 * @entry: the entry's RCU field 66 * 67 * Description: 68 * This function is designed to be used as a callback to the call_rcu() 69 * function so that the memory allocated to a hash table entry can be released 70 * safely. 71 * 72 */ 73 static void netlbl_domhsh_free_entry(struct rcu_head *entry) 74 { 75 struct netlbl_dom_map *ptr; 76 struct netlbl_af4list *iter4; 77 struct netlbl_af4list *tmp4; 78 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 79 struct netlbl_af6list *iter6; 80 struct netlbl_af6list *tmp6; 81 #endif /* IPv6 */ 82 83 ptr = container_of(entry, struct netlbl_dom_map, rcu); 84 if (ptr->type == NETLBL_NLTYPE_ADDRSELECT) { 85 netlbl_af4list_foreach_safe(iter4, tmp4, 86 &ptr->type_def.addrsel->list4) { 87 netlbl_af4list_remove_entry(iter4); 88 kfree(netlbl_domhsh_addr4_entry(iter4)); 89 } 90 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 91 netlbl_af6list_foreach_safe(iter6, tmp6, 92 &ptr->type_def.addrsel->list6) { 93 netlbl_af6list_remove_entry(iter6); 94 kfree(netlbl_domhsh_addr6_entry(iter6)); 95 } 96 #endif /* IPv6 */ 97 } 98 kfree(ptr->domain); 99 kfree(ptr); 100 } 101 102 /** 103 * netlbl_domhsh_hash - Hashing function for the domain hash table 104 * @domain: the domain name to hash 105 * 106 * Description: 107 * This is the hashing function for the domain hash table, it returns the 108 * correct bucket number for the domain. The caller is responsibile for 109 * calling the rcu_read_[un]lock() functions. 110 * 111 */ 112 static u32 netlbl_domhsh_hash(const char *key) 113 { 114 u32 iter; 115 u32 val; 116 u32 len; 117 118 /* This is taken (with slight modification) from 119 * security/selinux/ss/symtab.c:symhash() */ 120 121 for (iter = 0, val = 0, len = strlen(key); iter < len; iter++) 122 val = (val << 4 | (val >> (8 * sizeof(u32) - 4))) ^ key[iter]; 123 return val & (rcu_dereference(netlbl_domhsh)->size - 1); 124 } 125 126 /** 127 * netlbl_domhsh_search - Search for a domain entry 128 * @domain: the domain 129 * 130 * Description: 131 * Searches the domain hash table and returns a pointer to the hash table 132 * entry if found, otherwise NULL is returned. The caller is responsibile for 133 * the rcu hash table locks (i.e. the caller much call rcu_read_[un]lock()). 134 * 135 */ 136 static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain) 137 { 138 u32 bkt; 139 struct list_head *bkt_list; 140 struct netlbl_dom_map *iter; 141 142 if (domain != NULL) { 143 bkt = netlbl_domhsh_hash(domain); 144 bkt_list = &rcu_dereference(netlbl_domhsh)->tbl[bkt]; 145 list_for_each_entry_rcu(iter, bkt_list, list) 146 if (iter->valid && strcmp(iter->domain, domain) == 0) 147 return iter; 148 } 149 150 return NULL; 151 } 152 153 /** 154 * netlbl_domhsh_search_def - Search for a domain entry 155 * @domain: the domain 156 * @def: return default if no match is found 157 * 158 * Description: 159 * Searches the domain hash table and returns a pointer to the hash table 160 * entry if an exact match is found, if an exact match is not present in the 161 * hash table then the default entry is returned if valid otherwise NULL is 162 * returned. The caller is responsibile for the rcu hash table locks 163 * (i.e. the caller much call rcu_read_[un]lock()). 164 * 165 */ 166 static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain) 167 { 168 struct netlbl_dom_map *entry; 169 170 entry = netlbl_domhsh_search(domain); 171 if (entry == NULL) { 172 entry = rcu_dereference(netlbl_domhsh_def); 173 if (entry != NULL && !entry->valid) 174 entry = NULL; 175 } 176 177 return entry; 178 } 179 180 /** 181 * netlbl_domhsh_audit_add - Generate an audit entry for an add event 182 * @entry: the entry being added 183 * @addr4: the IPv4 address information 184 * @addr6: the IPv6 address information 185 * @result: the result code 186 * @audit_info: NetLabel audit information 187 * 188 * Description: 189 * Generate an audit record for adding a new NetLabel/LSM mapping entry with 190 * the given information. Caller is responsibile for holding the necessary 191 * locks. 192 * 193 */ 194 static void netlbl_domhsh_audit_add(struct netlbl_dom_map *entry, 195 struct netlbl_af4list *addr4, 196 struct netlbl_af6list *addr6, 197 int result, 198 struct netlbl_audit *audit_info) 199 { 200 struct audit_buffer *audit_buf; 201 struct cipso_v4_doi *cipsov4 = NULL; 202 u32 type; 203 204 audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info); 205 if (audit_buf != NULL) { 206 audit_log_format(audit_buf, " nlbl_domain=%s", 207 entry->domain ? entry->domain : "(default)"); 208 if (addr4 != NULL) { 209 struct netlbl_domaddr4_map *map4; 210 map4 = netlbl_domhsh_addr4_entry(addr4); 211 type = map4->type; 212 cipsov4 = map4->type_def.cipsov4; 213 netlbl_af4list_audit_addr(audit_buf, 0, NULL, 214 addr4->addr, addr4->mask); 215 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 216 } else if (addr6 != NULL) { 217 struct netlbl_domaddr6_map *map6; 218 map6 = netlbl_domhsh_addr6_entry(addr6); 219 type = map6->type; 220 netlbl_af6list_audit_addr(audit_buf, 0, NULL, 221 &addr6->addr, &addr6->mask); 222 #endif /* IPv6 */ 223 } else { 224 type = entry->type; 225 cipsov4 = entry->type_def.cipsov4; 226 } 227 switch (type) { 228 case NETLBL_NLTYPE_UNLABELED: 229 audit_log_format(audit_buf, " nlbl_protocol=unlbl"); 230 break; 231 case NETLBL_NLTYPE_CIPSOV4: 232 BUG_ON(cipsov4 == NULL); 233 audit_log_format(audit_buf, 234 " nlbl_protocol=cipsov4 cipso_doi=%u", 235 cipsov4->doi); 236 break; 237 } 238 audit_log_format(audit_buf, " res=%u", result == 0 ? 1 : 0); 239 audit_log_end(audit_buf); 240 } 241 } 242 243 /* 244 * Domain Hash Table Functions 245 */ 246 247 /** 248 * netlbl_domhsh_init - Init for the domain hash 249 * @size: the number of bits to use for the hash buckets 250 * 251 * Description: 252 * Initializes the domain hash table, should be called only by 253 * netlbl_user_init() during initialization. Returns zero on success, non-zero 254 * values on error. 255 * 256 */ 257 int __init netlbl_domhsh_init(u32 size) 258 { 259 u32 iter; 260 struct netlbl_domhsh_tbl *hsh_tbl; 261 262 if (size == 0) 263 return -EINVAL; 264 265 hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL); 266 if (hsh_tbl == NULL) 267 return -ENOMEM; 268 hsh_tbl->size = 1 << size; 269 hsh_tbl->tbl = kcalloc(hsh_tbl->size, 270 sizeof(struct list_head), 271 GFP_KERNEL); 272 if (hsh_tbl->tbl == NULL) { 273 kfree(hsh_tbl); 274 return -ENOMEM; 275 } 276 for (iter = 0; iter < hsh_tbl->size; iter++) 277 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]); 278 279 spin_lock(&netlbl_domhsh_lock); 280 rcu_assign_pointer(netlbl_domhsh, hsh_tbl); 281 spin_unlock(&netlbl_domhsh_lock); 282 283 return 0; 284 } 285 286 /** 287 * netlbl_domhsh_add - Adds a entry to the domain hash table 288 * @entry: the entry to add 289 * @audit_info: NetLabel audit information 290 * 291 * Description: 292 * Adds a new entry to the domain hash table and handles any updates to the 293 * lower level protocol handler (i.e. CIPSO). Returns zero on success, 294 * negative on failure. 295 * 296 */ 297 int netlbl_domhsh_add(struct netlbl_dom_map *entry, 298 struct netlbl_audit *audit_info) 299 { 300 int ret_val = 0; 301 struct netlbl_dom_map *entry_old; 302 struct netlbl_af4list *iter4; 303 struct netlbl_af4list *tmp4; 304 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 305 struct netlbl_af6list *iter6; 306 struct netlbl_af6list *tmp6; 307 #endif /* IPv6 */ 308 309 rcu_read_lock(); 310 311 spin_lock(&netlbl_domhsh_lock); 312 if (entry->domain != NULL) 313 entry_old = netlbl_domhsh_search(entry->domain); 314 else 315 entry_old = netlbl_domhsh_search_def(entry->domain); 316 if (entry_old == NULL) { 317 entry->valid = 1; 318 INIT_RCU_HEAD(&entry->rcu); 319 320 if (entry->domain != NULL) { 321 u32 bkt = netlbl_domhsh_hash(entry->domain); 322 list_add_tail_rcu(&entry->list, 323 &rcu_dereference(netlbl_domhsh)->tbl[bkt]); 324 } else { 325 INIT_LIST_HEAD(&entry->list); 326 rcu_assign_pointer(netlbl_domhsh_def, entry); 327 } 328 329 if (entry->type == NETLBL_NLTYPE_ADDRSELECT) { 330 netlbl_af4list_foreach_rcu(iter4, 331 &entry->type_def.addrsel->list4) 332 netlbl_domhsh_audit_add(entry, iter4, NULL, 333 ret_val, audit_info); 334 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 335 netlbl_af6list_foreach_rcu(iter6, 336 &entry->type_def.addrsel->list6) 337 netlbl_domhsh_audit_add(entry, NULL, iter6, 338 ret_val, audit_info); 339 #endif /* IPv6 */ 340 } else 341 netlbl_domhsh_audit_add(entry, NULL, NULL, 342 ret_val, audit_info); 343 } else if (entry_old->type == NETLBL_NLTYPE_ADDRSELECT && 344 entry->type == NETLBL_NLTYPE_ADDRSELECT) { 345 struct list_head *old_list4; 346 struct list_head *old_list6; 347 348 old_list4 = &entry_old->type_def.addrsel->list4; 349 old_list6 = &entry_old->type_def.addrsel->list6; 350 351 /* we only allow the addition of address selectors if all of 352 * the selectors do not exist in the existing domain map */ 353 netlbl_af4list_foreach_rcu(iter4, 354 &entry->type_def.addrsel->list4) 355 if (netlbl_af4list_search_exact(iter4->addr, 356 iter4->mask, 357 old_list4)) { 358 ret_val = -EEXIST; 359 goto add_return; 360 } 361 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 362 netlbl_af6list_foreach_rcu(iter6, 363 &entry->type_def.addrsel->list6) 364 if (netlbl_af6list_search_exact(&iter6->addr, 365 &iter6->mask, 366 old_list6)) { 367 ret_val = -EEXIST; 368 goto add_return; 369 } 370 #endif /* IPv6 */ 371 372 netlbl_af4list_foreach_safe(iter4, tmp4, 373 &entry->type_def.addrsel->list4) { 374 netlbl_af4list_remove_entry(iter4); 375 iter4->valid = 1; 376 ret_val = netlbl_af4list_add(iter4, old_list4); 377 netlbl_domhsh_audit_add(entry_old, iter4, NULL, 378 ret_val, audit_info); 379 if (ret_val != 0) 380 goto add_return; 381 } 382 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 383 netlbl_af6list_foreach_safe(iter6, tmp6, 384 &entry->type_def.addrsel->list6) { 385 netlbl_af6list_remove_entry(iter6); 386 iter6->valid = 1; 387 ret_val = netlbl_af6list_add(iter6, old_list6); 388 netlbl_domhsh_audit_add(entry_old, NULL, iter6, 389 ret_val, audit_info); 390 if (ret_val != 0) 391 goto add_return; 392 } 393 #endif /* IPv6 */ 394 } else 395 ret_val = -EINVAL; 396 397 add_return: 398 spin_unlock(&netlbl_domhsh_lock); 399 rcu_read_unlock(); 400 return ret_val; 401 } 402 403 /** 404 * netlbl_domhsh_add_default - Adds the default entry to the domain hash table 405 * @entry: the entry to add 406 * @audit_info: NetLabel audit information 407 * 408 * Description: 409 * Adds a new default entry to the domain hash table and handles any updates 410 * to the lower level protocol handler (i.e. CIPSO). Returns zero on success, 411 * negative on failure. 412 * 413 */ 414 int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, 415 struct netlbl_audit *audit_info) 416 { 417 return netlbl_domhsh_add(entry, audit_info); 418 } 419 420 /** 421 * netlbl_domhsh_remove_entry - Removes a given entry from the domain table 422 * @entry: the entry to remove 423 * @audit_info: NetLabel audit information 424 * 425 * Description: 426 * Removes an entry from the domain hash table and handles any updates to the 427 * lower level protocol handler (i.e. CIPSO). Caller is responsible for 428 * ensuring that the RCU read lock is held. Returns zero on success, negative 429 * on failure. 430 * 431 */ 432 int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, 433 struct netlbl_audit *audit_info) 434 { 435 int ret_val = 0; 436 struct audit_buffer *audit_buf; 437 438 if (entry == NULL) 439 return -ENOENT; 440 441 spin_lock(&netlbl_domhsh_lock); 442 if (entry->valid) { 443 entry->valid = 0; 444 if (entry != rcu_dereference(netlbl_domhsh_def)) 445 list_del_rcu(&entry->list); 446 else 447 rcu_assign_pointer(netlbl_domhsh_def, NULL); 448 } else 449 ret_val = -ENOENT; 450 spin_unlock(&netlbl_domhsh_lock); 451 452 audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info); 453 if (audit_buf != NULL) { 454 audit_log_format(audit_buf, 455 " nlbl_domain=%s res=%u", 456 entry->domain ? entry->domain : "(default)", 457 ret_val == 0 ? 1 : 0); 458 audit_log_end(audit_buf); 459 } 460 461 if (ret_val == 0) { 462 struct netlbl_af4list *iter4; 463 struct netlbl_domaddr4_map *map4; 464 465 switch (entry->type) { 466 case NETLBL_NLTYPE_ADDRSELECT: 467 netlbl_af4list_foreach_rcu(iter4, 468 &entry->type_def.addrsel->list4) { 469 map4 = netlbl_domhsh_addr4_entry(iter4); 470 cipso_v4_doi_putdef(map4->type_def.cipsov4); 471 } 472 /* no need to check the IPv6 list since we currently 473 * support only unlabeled protocols for IPv6 */ 474 break; 475 case NETLBL_NLTYPE_CIPSOV4: 476 cipso_v4_doi_putdef(entry->type_def.cipsov4); 477 break; 478 } 479 call_rcu(&entry->rcu, netlbl_domhsh_free_entry); 480 } 481 482 return ret_val; 483 } 484 485 /** 486 * netlbl_domhsh_remove_af4 - Removes an address selector entry 487 * @domain: the domain 488 * @addr: IPv4 address 489 * @mask: IPv4 address mask 490 * @audit_info: NetLabel audit information 491 * 492 * Description: 493 * Removes an individual address selector from a domain mapping and potentially 494 * the entire mapping if it is empty. Returns zero on success, negative values 495 * on failure. 496 * 497 */ 498 int netlbl_domhsh_remove_af4(const char *domain, 499 const struct in_addr *addr, 500 const struct in_addr *mask, 501 struct netlbl_audit *audit_info) 502 { 503 struct netlbl_dom_map *entry_map; 504 struct netlbl_af4list *entry_addr; 505 struct netlbl_af4list *iter4; 506 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 507 struct netlbl_af6list *iter6; 508 #endif /* IPv6 */ 509 struct netlbl_domaddr4_map *entry; 510 511 rcu_read_lock(); 512 513 if (domain) 514 entry_map = netlbl_domhsh_search(domain); 515 else 516 entry_map = netlbl_domhsh_search_def(domain); 517 if (entry_map == NULL || entry_map->type != NETLBL_NLTYPE_ADDRSELECT) 518 goto remove_af4_failure; 519 520 spin_lock(&netlbl_domhsh_lock); 521 entry_addr = netlbl_af4list_remove(addr->s_addr, mask->s_addr, 522 &entry_map->type_def.addrsel->list4); 523 spin_unlock(&netlbl_domhsh_lock); 524 525 if (entry_addr == NULL) 526 goto remove_af4_failure; 527 netlbl_af4list_foreach_rcu(iter4, &entry_map->type_def.addrsel->list4) 528 goto remove_af4_single_addr; 529 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 530 netlbl_af6list_foreach_rcu(iter6, &entry_map->type_def.addrsel->list6) 531 goto remove_af4_single_addr; 532 #endif /* IPv6 */ 533 /* the domain mapping is empty so remove it from the mapping table */ 534 netlbl_domhsh_remove_entry(entry_map, audit_info); 535 536 remove_af4_single_addr: 537 rcu_read_unlock(); 538 /* yick, we can't use call_rcu here because we don't have a rcu head 539 * pointer but hopefully this should be a rare case so the pause 540 * shouldn't be a problem */ 541 synchronize_rcu(); 542 entry = netlbl_domhsh_addr4_entry(entry_addr); 543 cipso_v4_doi_putdef(entry->type_def.cipsov4); 544 kfree(entry); 545 return 0; 546 547 remove_af4_failure: 548 rcu_read_unlock(); 549 return -ENOENT; 550 } 551 552 /** 553 * netlbl_domhsh_remove - Removes an entry from the domain hash table 554 * @domain: the domain to remove 555 * @audit_info: NetLabel audit information 556 * 557 * Description: 558 * Removes an entry from the domain hash table and handles any updates to the 559 * lower level protocol handler (i.e. CIPSO). Returns zero on success, 560 * negative on failure. 561 * 562 */ 563 int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info) 564 { 565 int ret_val; 566 struct netlbl_dom_map *entry; 567 568 rcu_read_lock(); 569 if (domain) 570 entry = netlbl_domhsh_search(domain); 571 else 572 entry = netlbl_domhsh_search_def(domain); 573 ret_val = netlbl_domhsh_remove_entry(entry, audit_info); 574 rcu_read_unlock(); 575 576 return ret_val; 577 } 578 579 /** 580 * netlbl_domhsh_remove_default - Removes the default entry from the table 581 * @audit_info: NetLabel audit information 582 * 583 * Description: 584 * Removes/resets the default entry for the domain hash table and handles any 585 * updates to the lower level protocol handler (i.e. CIPSO). Returns zero on 586 * success, non-zero on failure. 587 * 588 */ 589 int netlbl_domhsh_remove_default(struct netlbl_audit *audit_info) 590 { 591 return netlbl_domhsh_remove(NULL, audit_info); 592 } 593 594 /** 595 * netlbl_domhsh_getentry - Get an entry from the domain hash table 596 * @domain: the domain name to search for 597 * 598 * Description: 599 * Look through the domain hash table searching for an entry to match @domain, 600 * return a pointer to a copy of the entry or NULL. The caller is responsibile 601 * for ensuring that rcu_read_[un]lock() is called. 602 * 603 */ 604 struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain) 605 { 606 return netlbl_domhsh_search_def(domain); 607 } 608 609 /** 610 * netlbl_domhsh_getentry_af4 - Get an entry from the domain hash table 611 * @domain: the domain name to search for 612 * @addr: the IP address to search for 613 * 614 * Description: 615 * Look through the domain hash table searching for an entry to match @domain 616 * and @addr, return a pointer to a copy of the entry or NULL. The caller is 617 * responsible for ensuring that rcu_read_[un]lock() is called. 618 * 619 */ 620 struct netlbl_domaddr4_map *netlbl_domhsh_getentry_af4(const char *domain, 621 __be32 addr) 622 { 623 struct netlbl_dom_map *dom_iter; 624 struct netlbl_af4list *addr_iter; 625 626 dom_iter = netlbl_domhsh_search_def(domain); 627 if (dom_iter == NULL) 628 return NULL; 629 if (dom_iter->type != NETLBL_NLTYPE_ADDRSELECT) 630 return NULL; 631 632 addr_iter = netlbl_af4list_search(addr, 633 &dom_iter->type_def.addrsel->list4); 634 if (addr_iter == NULL) 635 return NULL; 636 637 return netlbl_domhsh_addr4_entry(addr_iter); 638 } 639 640 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 641 /** 642 * netlbl_domhsh_getentry_af6 - Get an entry from the domain hash table 643 * @domain: the domain name to search for 644 * @addr: the IP address to search for 645 * 646 * Description: 647 * Look through the domain hash table searching for an entry to match @domain 648 * and @addr, return a pointer to a copy of the entry or NULL. The caller is 649 * responsible for ensuring that rcu_read_[un]lock() is called. 650 * 651 */ 652 struct netlbl_domaddr6_map *netlbl_domhsh_getentry_af6(const char *domain, 653 const struct in6_addr *addr) 654 { 655 struct netlbl_dom_map *dom_iter; 656 struct netlbl_af6list *addr_iter; 657 658 dom_iter = netlbl_domhsh_search_def(domain); 659 if (dom_iter == NULL) 660 return NULL; 661 if (dom_iter->type != NETLBL_NLTYPE_ADDRSELECT) 662 return NULL; 663 664 addr_iter = netlbl_af6list_search(addr, 665 &dom_iter->type_def.addrsel->list6); 666 if (addr_iter == NULL) 667 return NULL; 668 669 return netlbl_domhsh_addr6_entry(addr_iter); 670 } 671 #endif /* IPv6 */ 672 673 /** 674 * netlbl_domhsh_walk - Iterate through the domain mapping hash table 675 * @skip_bkt: the number of buckets to skip at the start 676 * @skip_chain: the number of entries to skip in the first iterated bucket 677 * @callback: callback for each entry 678 * @cb_arg: argument for the callback function 679 * 680 * Description: 681 * Interate over the domain mapping hash table, skipping the first @skip_bkt 682 * buckets and @skip_chain entries. For each entry in the table call 683 * @callback, if @callback returns a negative value stop 'walking' through the 684 * table and return. Updates the values in @skip_bkt and @skip_chain on 685 * return. Returns zero on success, negative values on failure. 686 * 687 */ 688 int netlbl_domhsh_walk(u32 *skip_bkt, 689 u32 *skip_chain, 690 int (*callback) (struct netlbl_dom_map *entry, void *arg), 691 void *cb_arg) 692 { 693 int ret_val = -ENOENT; 694 u32 iter_bkt; 695 struct list_head *iter_list; 696 struct netlbl_dom_map *iter_entry; 697 u32 chain_cnt = 0; 698 699 rcu_read_lock(); 700 for (iter_bkt = *skip_bkt; 701 iter_bkt < rcu_dereference(netlbl_domhsh)->size; 702 iter_bkt++, chain_cnt = 0) { 703 iter_list = &rcu_dereference(netlbl_domhsh)->tbl[iter_bkt]; 704 list_for_each_entry_rcu(iter_entry, iter_list, list) 705 if (iter_entry->valid) { 706 if (chain_cnt++ < *skip_chain) 707 continue; 708 ret_val = callback(iter_entry, cb_arg); 709 if (ret_val < 0) { 710 chain_cnt--; 711 goto walk_return; 712 } 713 } 714 } 715 716 walk_return: 717 rcu_read_unlock(); 718 *skip_bkt = iter_bkt; 719 *skip_chain = chain_cnt; 720 return ret_val; 721 } 722