1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * NetLabel Domain Hash Table |
4 | * |
5 | * This file manages the domain hash table that NetLabel uses to determine |
6 | * which network labeling protocol to use for a given domain. The NetLabel |
7 | * system manages static and dynamic label mappings for network protocols such |
8 | * as CIPSO and RIPSO. |
9 | * |
10 | * Author: Paul Moore <paul@paul-moore.com> |
11 | */ |
12 | |
13 | /* |
14 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 |
15 | */ |
16 | |
17 | #include <linux/types.h> |
18 | #include <linux/rculist.h> |
19 | #include <linux/skbuff.h> |
20 | #include <linux/spinlock.h> |
21 | #include <linux/string.h> |
22 | #include <linux/audit.h> |
23 | #include <linux/slab.h> |
24 | #include <net/netlabel.h> |
25 | #include <net/cipso_ipv4.h> |
26 | #include <net/calipso.h> |
27 | #include <asm/bug.h> |
28 | |
29 | #include "netlabel_mgmt.h" |
30 | #include "netlabel_addrlist.h" |
31 | #include "netlabel_calipso.h" |
32 | #include "netlabel_domainhash.h" |
33 | #include "netlabel_user.h" |
34 | |
35 | struct netlbl_domhsh_tbl { |
36 | struct list_head *tbl; |
37 | u32 size; |
38 | }; |
39 | |
40 | /* Domain hash table */ |
41 | /* updates should be so rare that having one spinlock for the entire hash table |
42 | * should be okay */ |
43 | static DEFINE_SPINLOCK(netlbl_domhsh_lock); |
44 | #define netlbl_domhsh_rcu_deref(p) \ |
45 | rcu_dereference_check(p, lockdep_is_held(&netlbl_domhsh_lock)) |
46 | static struct netlbl_domhsh_tbl __rcu *netlbl_domhsh; |
47 | static struct netlbl_dom_map __rcu *netlbl_domhsh_def_ipv4; |
48 | static struct netlbl_dom_map __rcu *netlbl_domhsh_def_ipv6; |
49 | |
50 | /* |
51 | * Domain Hash Table Helper Functions |
52 | */ |
53 | |
54 | /** |
55 | * netlbl_domhsh_free_entry - Frees a domain hash table entry |
56 | * @entry: the entry's RCU field |
57 | * |
58 | * Description: |
59 | * This function is designed to be used as a callback to the call_rcu() |
60 | * function so that the memory allocated to a hash table entry can be released |
61 | * safely. |
62 | * |
63 | */ |
64 | static void netlbl_domhsh_free_entry(struct rcu_head *entry) |
65 | { |
66 | struct netlbl_dom_map *ptr; |
67 | struct netlbl_af4list *iter4; |
68 | struct netlbl_af4list *tmp4; |
69 | #if IS_ENABLED(CONFIG_IPV6) |
70 | struct netlbl_af6list *iter6; |
71 | struct netlbl_af6list *tmp6; |
72 | #endif /* IPv6 */ |
73 | |
74 | ptr = container_of(entry, struct netlbl_dom_map, rcu); |
75 | if (ptr->def.type == NETLBL_NLTYPE_ADDRSELECT) { |
76 | netlbl_af4list_foreach_safe(iter4, tmp4, |
77 | &ptr->def.addrsel->list4) { |
78 | netlbl_af4list_remove_entry(entry: iter4); |
79 | kfree(netlbl_domhsh_addr4_entry(iter4)); |
80 | } |
81 | #if IS_ENABLED(CONFIG_IPV6) |
82 | netlbl_af6list_foreach_safe(iter6, tmp6, |
83 | &ptr->def.addrsel->list6) { |
84 | netlbl_af6list_remove_entry(entry: iter6); |
85 | kfree(netlbl_domhsh_addr6_entry(iter6)); |
86 | } |
87 | #endif /* IPv6 */ |
88 | kfree(objp: ptr->def.addrsel); |
89 | } |
90 | kfree(objp: ptr->domain); |
91 | kfree(objp: ptr); |
92 | } |
93 | |
94 | /** |
95 | * netlbl_domhsh_hash - Hashing function for the domain hash table |
96 | * @key: the domain name to hash |
97 | * |
98 | * Description: |
99 | * This is the hashing function for the domain hash table, it returns the |
100 | * correct bucket number for the domain. The caller is responsible for |
101 | * ensuring that the hash table is protected with either a RCU read lock or the |
102 | * hash table lock. |
103 | * |
104 | */ |
105 | static u32 netlbl_domhsh_hash(const char *key) |
106 | { |
107 | u32 iter; |
108 | u32 val; |
109 | u32 len; |
110 | |
111 | /* This is taken (with slight modification) from |
112 | * security/selinux/ss/symtab.c:symhash() */ |
113 | |
114 | for (iter = 0, val = 0, len = strlen(key); iter < len; iter++) |
115 | val = (val << 4 | (val >> (8 * sizeof(u32) - 4))) ^ key[iter]; |
116 | return val & (netlbl_domhsh_rcu_deref(netlbl_domhsh)->size - 1); |
117 | } |
118 | |
119 | static bool netlbl_family_match(u16 f1, u16 f2) |
120 | { |
121 | return (f1 == f2) || (f1 == AF_UNSPEC) || (f2 == AF_UNSPEC); |
122 | } |
123 | |
124 | /** |
125 | * netlbl_domhsh_search - Search for a domain entry |
126 | * @domain: the domain |
127 | * @family: the address family |
128 | * |
129 | * Description: |
130 | * Searches the domain hash table and returns a pointer to the hash table |
131 | * entry if found, otherwise NULL is returned. @family may be %AF_UNSPEC |
132 | * which matches any address family entries. The caller is responsible for |
133 | * ensuring that the hash table is protected with either a RCU read lock or the |
134 | * hash table lock. |
135 | * |
136 | */ |
137 | static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain, |
138 | u16 family) |
139 | { |
140 | u32 bkt; |
141 | struct list_head *bkt_list; |
142 | struct netlbl_dom_map *iter; |
143 | |
144 | if (domain != NULL) { |
145 | bkt = netlbl_domhsh_hash(key: domain); |
146 | bkt_list = &netlbl_domhsh_rcu_deref(netlbl_domhsh)->tbl[bkt]; |
147 | list_for_each_entry_rcu(iter, bkt_list, list, |
148 | lockdep_is_held(&netlbl_domhsh_lock)) |
149 | if (iter->valid && |
150 | netlbl_family_match(f1: iter->family, f2: family) && |
151 | strcmp(iter->domain, domain) == 0) |
152 | return iter; |
153 | } |
154 | |
155 | return NULL; |
156 | } |
157 | |
158 | /** |
159 | * netlbl_domhsh_search_def - Search for a domain entry |
160 | * @domain: the domain |
161 | * @family: the address family |
162 | * |
163 | * Description: |
164 | * Searches the domain hash table and returns a pointer to the hash table |
165 | * entry if an exact match is found, if an exact match is not present in the |
166 | * hash table then the default entry is returned if valid otherwise NULL is |
167 | * returned. @family may be %AF_UNSPEC which matches any address family |
168 | * entries. The caller is responsible ensuring that the hash table is |
169 | * protected with either a RCU read lock or the hash table lock. |
170 | * |
171 | */ |
172 | static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain, |
173 | u16 family) |
174 | { |
175 | struct netlbl_dom_map *entry; |
176 | |
177 | entry = netlbl_domhsh_search(domain, family); |
178 | if (entry != NULL) |
179 | return entry; |
180 | if (family == AF_INET || family == AF_UNSPEC) { |
181 | entry = netlbl_domhsh_rcu_deref(netlbl_domhsh_def_ipv4); |
182 | if (entry != NULL && entry->valid) |
183 | return entry; |
184 | } |
185 | if (family == AF_INET6 || family == AF_UNSPEC) { |
186 | entry = netlbl_domhsh_rcu_deref(netlbl_domhsh_def_ipv6); |
187 | if (entry != NULL && entry->valid) |
188 | return entry; |
189 | } |
190 | |
191 | return NULL; |
192 | } |
193 | |
194 | /** |
195 | * netlbl_domhsh_audit_add - Generate an audit entry for an add event |
196 | * @entry: the entry being added |
197 | * @addr4: the IPv4 address information |
198 | * @addr6: the IPv6 address information |
199 | * @result: the result code |
200 | * @audit_info: NetLabel audit information |
201 | * |
202 | * Description: |
203 | * Generate an audit record for adding a new NetLabel/LSM mapping entry with |
204 | * the given information. Caller is responsible for holding the necessary |
205 | * locks. |
206 | * |
207 | */ |
208 | static void netlbl_domhsh_audit_add(struct netlbl_dom_map *entry, |
209 | struct netlbl_af4list *addr4, |
210 | struct netlbl_af6list *addr6, |
211 | int result, |
212 | struct netlbl_audit *audit_info) |
213 | { |
214 | struct audit_buffer *audit_buf; |
215 | struct cipso_v4_doi *cipsov4 = NULL; |
216 | struct calipso_doi *calipso = NULL; |
217 | u32 type; |
218 | |
219 | audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info); |
220 | if (audit_buf != NULL) { |
221 | audit_log_format(ab: audit_buf, fmt: " nlbl_domain=%s" , |
222 | entry->domain ? entry->domain : "(default)" ); |
223 | if (addr4 != NULL) { |
224 | struct netlbl_domaddr4_map *map4; |
225 | map4 = netlbl_domhsh_addr4_entry(addr4); |
226 | type = map4->def.type; |
227 | cipsov4 = map4->def.cipso; |
228 | netlbl_af4list_audit_addr(audit_buf, src: 0, NULL, |
229 | addr: addr4->addr, mask: addr4->mask); |
230 | #if IS_ENABLED(CONFIG_IPV6) |
231 | } else if (addr6 != NULL) { |
232 | struct netlbl_domaddr6_map *map6; |
233 | map6 = netlbl_domhsh_addr6_entry(addr6); |
234 | type = map6->def.type; |
235 | calipso = map6->def.calipso; |
236 | netlbl_af6list_audit_addr(audit_buf, src: 0, NULL, |
237 | addr: &addr6->addr, mask: &addr6->mask); |
238 | #endif /* IPv6 */ |
239 | } else { |
240 | type = entry->def.type; |
241 | cipsov4 = entry->def.cipso; |
242 | calipso = entry->def.calipso; |
243 | } |
244 | switch (type) { |
245 | case NETLBL_NLTYPE_UNLABELED: |
246 | audit_log_format(ab: audit_buf, fmt: " nlbl_protocol=unlbl" ); |
247 | break; |
248 | case NETLBL_NLTYPE_CIPSOV4: |
249 | BUG_ON(cipsov4 == NULL); |
250 | audit_log_format(ab: audit_buf, |
251 | fmt: " nlbl_protocol=cipsov4 cipso_doi=%u" , |
252 | cipsov4->doi); |
253 | break; |
254 | case NETLBL_NLTYPE_CALIPSO: |
255 | BUG_ON(calipso == NULL); |
256 | audit_log_format(ab: audit_buf, |
257 | fmt: " nlbl_protocol=calipso calipso_doi=%u" , |
258 | calipso->doi); |
259 | break; |
260 | } |
261 | audit_log_format(ab: audit_buf, fmt: " res=%u" , result == 0 ? 1 : 0); |
262 | audit_log_end(ab: audit_buf); |
263 | } |
264 | } |
265 | |
266 | /** |
267 | * netlbl_domhsh_validate - Validate a new domain mapping entry |
268 | * @entry: the entry to validate |
269 | * |
270 | * This function validates the new domain mapping entry to ensure that it is |
271 | * a valid entry. Returns zero on success, negative values on failure. |
272 | * |
273 | */ |
274 | static int netlbl_domhsh_validate(const struct netlbl_dom_map *entry) |
275 | { |
276 | struct netlbl_af4list *iter4; |
277 | struct netlbl_domaddr4_map *map4; |
278 | #if IS_ENABLED(CONFIG_IPV6) |
279 | struct netlbl_af6list *iter6; |
280 | struct netlbl_domaddr6_map *map6; |
281 | #endif /* IPv6 */ |
282 | |
283 | if (entry == NULL) |
284 | return -EINVAL; |
285 | |
286 | if (entry->family != AF_INET && entry->family != AF_INET6 && |
287 | (entry->family != AF_UNSPEC || |
288 | entry->def.type != NETLBL_NLTYPE_UNLABELED)) |
289 | return -EINVAL; |
290 | |
291 | switch (entry->def.type) { |
292 | case NETLBL_NLTYPE_UNLABELED: |
293 | if (entry->def.cipso != NULL || entry->def.calipso != NULL || |
294 | entry->def.addrsel != NULL) |
295 | return -EINVAL; |
296 | break; |
297 | case NETLBL_NLTYPE_CIPSOV4: |
298 | if (entry->family != AF_INET || |
299 | entry->def.cipso == NULL) |
300 | return -EINVAL; |
301 | break; |
302 | case NETLBL_NLTYPE_CALIPSO: |
303 | if (entry->family != AF_INET6 || |
304 | entry->def.calipso == NULL) |
305 | return -EINVAL; |
306 | break; |
307 | case NETLBL_NLTYPE_ADDRSELECT: |
308 | netlbl_af4list_foreach(iter4, &entry->def.addrsel->list4) { |
309 | map4 = netlbl_domhsh_addr4_entry(iter4); |
310 | switch (map4->def.type) { |
311 | case NETLBL_NLTYPE_UNLABELED: |
312 | if (map4->def.cipso != NULL) |
313 | return -EINVAL; |
314 | break; |
315 | case NETLBL_NLTYPE_CIPSOV4: |
316 | if (map4->def.cipso == NULL) |
317 | return -EINVAL; |
318 | break; |
319 | default: |
320 | return -EINVAL; |
321 | } |
322 | } |
323 | #if IS_ENABLED(CONFIG_IPV6) |
324 | netlbl_af6list_foreach(iter6, &entry->def.addrsel->list6) { |
325 | map6 = netlbl_domhsh_addr6_entry(iter6); |
326 | switch (map6->def.type) { |
327 | case NETLBL_NLTYPE_UNLABELED: |
328 | if (map6->def.calipso != NULL) |
329 | return -EINVAL; |
330 | break; |
331 | case NETLBL_NLTYPE_CALIPSO: |
332 | if (map6->def.calipso == NULL) |
333 | return -EINVAL; |
334 | break; |
335 | default: |
336 | return -EINVAL; |
337 | } |
338 | } |
339 | #endif /* IPv6 */ |
340 | break; |
341 | default: |
342 | return -EINVAL; |
343 | } |
344 | |
345 | return 0; |
346 | } |
347 | |
348 | /* |
349 | * Domain Hash Table Functions |
350 | */ |
351 | |
352 | /** |
353 | * netlbl_domhsh_init - Init for the domain hash |
354 | * @size: the number of bits to use for the hash buckets |
355 | * |
356 | * Description: |
357 | * Initializes the domain hash table, should be called only by |
358 | * netlbl_user_init() during initialization. Returns zero on success, non-zero |
359 | * values on error. |
360 | * |
361 | */ |
362 | int __init netlbl_domhsh_init(u32 size) |
363 | { |
364 | u32 iter; |
365 | struct netlbl_domhsh_tbl *hsh_tbl; |
366 | |
367 | if (size == 0) |
368 | return -EINVAL; |
369 | |
370 | hsh_tbl = kmalloc(size: sizeof(*hsh_tbl), GFP_KERNEL); |
371 | if (hsh_tbl == NULL) |
372 | return -ENOMEM; |
373 | hsh_tbl->size = 1 << size; |
374 | hsh_tbl->tbl = kcalloc(n: hsh_tbl->size, |
375 | size: sizeof(struct list_head), |
376 | GFP_KERNEL); |
377 | if (hsh_tbl->tbl == NULL) { |
378 | kfree(objp: hsh_tbl); |
379 | return -ENOMEM; |
380 | } |
381 | for (iter = 0; iter < hsh_tbl->size; iter++) |
382 | INIT_LIST_HEAD(list: &hsh_tbl->tbl[iter]); |
383 | |
384 | spin_lock(lock: &netlbl_domhsh_lock); |
385 | rcu_assign_pointer(netlbl_domhsh, hsh_tbl); |
386 | spin_unlock(lock: &netlbl_domhsh_lock); |
387 | |
388 | return 0; |
389 | } |
390 | |
391 | /** |
392 | * netlbl_domhsh_add - Adds a entry to the domain hash table |
393 | * @entry: the entry to add |
394 | * @audit_info: NetLabel audit information |
395 | * |
396 | * Description: |
397 | * Adds a new entry to the domain hash table and handles any updates to the |
398 | * lower level protocol handler (i.e. CIPSO). @entry->family may be set to |
399 | * %AF_UNSPEC which will add an entry that matches all address families. This |
400 | * is only useful for the unlabelled type and will only succeed if there is no |
401 | * existing entry for any address family with the same domain. Returns zero |
402 | * on success, negative on failure. |
403 | * |
404 | */ |
405 | int netlbl_domhsh_add(struct netlbl_dom_map *entry, |
406 | struct netlbl_audit *audit_info) |
407 | { |
408 | int ret_val = 0; |
409 | struct netlbl_dom_map *entry_old, *entry_b; |
410 | struct netlbl_af4list *iter4; |
411 | struct netlbl_af4list *tmp4; |
412 | #if IS_ENABLED(CONFIG_IPV6) |
413 | struct netlbl_af6list *iter6; |
414 | struct netlbl_af6list *tmp6; |
415 | #endif /* IPv6 */ |
416 | |
417 | ret_val = netlbl_domhsh_validate(entry); |
418 | if (ret_val != 0) |
419 | return ret_val; |
420 | |
421 | /* XXX - we can remove this RCU read lock as the spinlock protects the |
422 | * entire function, but before we do we need to fixup the |
423 | * netlbl_af[4,6]list RCU functions to do "the right thing" with |
424 | * respect to rcu_dereference() when only a spinlock is held. */ |
425 | rcu_read_lock(); |
426 | spin_lock(lock: &netlbl_domhsh_lock); |
427 | if (entry->domain != NULL) |
428 | entry_old = netlbl_domhsh_search(domain: entry->domain, family: entry->family); |
429 | else |
430 | entry_old = netlbl_domhsh_search_def(domain: entry->domain, |
431 | family: entry->family); |
432 | if (entry_old == NULL) { |
433 | entry->valid = 1; |
434 | |
435 | if (entry->domain != NULL) { |
436 | u32 bkt = netlbl_domhsh_hash(key: entry->domain); |
437 | list_add_tail_rcu(new: &entry->list, |
438 | head: &rcu_dereference(netlbl_domhsh)->tbl[bkt]); |
439 | } else { |
440 | INIT_LIST_HEAD(list: &entry->list); |
441 | switch (entry->family) { |
442 | case AF_INET: |
443 | rcu_assign_pointer(netlbl_domhsh_def_ipv4, |
444 | entry); |
445 | break; |
446 | case AF_INET6: |
447 | rcu_assign_pointer(netlbl_domhsh_def_ipv6, |
448 | entry); |
449 | break; |
450 | case AF_UNSPEC: |
451 | if (entry->def.type != |
452 | NETLBL_NLTYPE_UNLABELED) { |
453 | ret_val = -EINVAL; |
454 | goto add_return; |
455 | } |
456 | entry_b = kzalloc(size: sizeof(*entry_b), GFP_ATOMIC); |
457 | if (entry_b == NULL) { |
458 | ret_val = -ENOMEM; |
459 | goto add_return; |
460 | } |
461 | entry_b->family = AF_INET6; |
462 | entry_b->def.type = NETLBL_NLTYPE_UNLABELED; |
463 | entry_b->valid = 1; |
464 | entry->family = AF_INET; |
465 | rcu_assign_pointer(netlbl_domhsh_def_ipv4, |
466 | entry); |
467 | rcu_assign_pointer(netlbl_domhsh_def_ipv6, |
468 | entry_b); |
469 | break; |
470 | default: |
471 | /* Already checked in |
472 | * netlbl_domhsh_validate(). */ |
473 | ret_val = -EINVAL; |
474 | goto add_return; |
475 | } |
476 | } |
477 | |
478 | if (entry->def.type == NETLBL_NLTYPE_ADDRSELECT) { |
479 | netlbl_af4list_foreach_rcu(iter4, |
480 | &entry->def.addrsel->list4) |
481 | netlbl_domhsh_audit_add(entry, addr4: iter4, NULL, |
482 | result: ret_val, audit_info); |
483 | #if IS_ENABLED(CONFIG_IPV6) |
484 | netlbl_af6list_foreach_rcu(iter6, |
485 | &entry->def.addrsel->list6) |
486 | netlbl_domhsh_audit_add(entry, NULL, addr6: iter6, |
487 | result: ret_val, audit_info); |
488 | #endif /* IPv6 */ |
489 | } else |
490 | netlbl_domhsh_audit_add(entry, NULL, NULL, |
491 | result: ret_val, audit_info); |
492 | } else if (entry_old->def.type == NETLBL_NLTYPE_ADDRSELECT && |
493 | entry->def.type == NETLBL_NLTYPE_ADDRSELECT) { |
494 | struct list_head *old_list4; |
495 | struct list_head *old_list6; |
496 | |
497 | old_list4 = &entry_old->def.addrsel->list4; |
498 | old_list6 = &entry_old->def.addrsel->list6; |
499 | |
500 | /* we only allow the addition of address selectors if all of |
501 | * the selectors do not exist in the existing domain map */ |
502 | netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) |
503 | if (netlbl_af4list_search_exact(addr: iter4->addr, |
504 | mask: iter4->mask, |
505 | head: old_list4)) { |
506 | ret_val = -EEXIST; |
507 | goto add_return; |
508 | } |
509 | #if IS_ENABLED(CONFIG_IPV6) |
510 | netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) |
511 | if (netlbl_af6list_search_exact(addr: &iter6->addr, |
512 | mask: &iter6->mask, |
513 | head: old_list6)) { |
514 | ret_val = -EEXIST; |
515 | goto add_return; |
516 | } |
517 | #endif /* IPv6 */ |
518 | |
519 | netlbl_af4list_foreach_safe(iter4, tmp4, |
520 | &entry->def.addrsel->list4) { |
521 | netlbl_af4list_remove_entry(entry: iter4); |
522 | iter4->valid = 1; |
523 | ret_val = netlbl_af4list_add(entry: iter4, head: old_list4); |
524 | netlbl_domhsh_audit_add(entry: entry_old, addr4: iter4, NULL, |
525 | result: ret_val, audit_info); |
526 | if (ret_val != 0) |
527 | goto add_return; |
528 | } |
529 | #if IS_ENABLED(CONFIG_IPV6) |
530 | netlbl_af6list_foreach_safe(iter6, tmp6, |
531 | &entry->def.addrsel->list6) { |
532 | netlbl_af6list_remove_entry(entry: iter6); |
533 | iter6->valid = 1; |
534 | ret_val = netlbl_af6list_add(entry: iter6, head: old_list6); |
535 | netlbl_domhsh_audit_add(entry: entry_old, NULL, addr6: iter6, |
536 | result: ret_val, audit_info); |
537 | if (ret_val != 0) |
538 | goto add_return; |
539 | } |
540 | #endif /* IPv6 */ |
541 | /* cleanup the new entry since we've moved everything over */ |
542 | netlbl_domhsh_free_entry(entry: &entry->rcu); |
543 | } else |
544 | ret_val = -EINVAL; |
545 | |
546 | add_return: |
547 | spin_unlock(lock: &netlbl_domhsh_lock); |
548 | rcu_read_unlock(); |
549 | return ret_val; |
550 | } |
551 | |
552 | /** |
553 | * netlbl_domhsh_add_default - Adds the default entry to the domain hash table |
554 | * @entry: the entry to add |
555 | * @audit_info: NetLabel audit information |
556 | * |
557 | * Description: |
558 | * Adds a new default entry to the domain hash table and handles any updates |
559 | * to the lower level protocol handler (i.e. CIPSO). Returns zero on success, |
560 | * negative on failure. |
561 | * |
562 | */ |
563 | int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, |
564 | struct netlbl_audit *audit_info) |
565 | { |
566 | return netlbl_domhsh_add(entry, audit_info); |
567 | } |
568 | |
569 | /** |
570 | * netlbl_domhsh_remove_entry - Removes a given entry from the domain table |
571 | * @entry: the entry to remove |
572 | * @audit_info: NetLabel audit information |
573 | * |
574 | * Description: |
575 | * Removes an entry from the domain hash table and handles any updates to the |
576 | * lower level protocol handler (i.e. CIPSO). Caller is responsible for |
577 | * ensuring that the RCU read lock is held. Returns zero on success, negative |
578 | * on failure. |
579 | * |
580 | */ |
581 | int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, |
582 | struct netlbl_audit *audit_info) |
583 | { |
584 | int ret_val = 0; |
585 | struct audit_buffer *audit_buf; |
586 | struct netlbl_af4list *iter4; |
587 | struct netlbl_domaddr4_map *map4; |
588 | #if IS_ENABLED(CONFIG_IPV6) |
589 | struct netlbl_af6list *iter6; |
590 | struct netlbl_domaddr6_map *map6; |
591 | #endif /* IPv6 */ |
592 | |
593 | if (entry == NULL) |
594 | return -ENOENT; |
595 | |
596 | spin_lock(lock: &netlbl_domhsh_lock); |
597 | if (entry->valid) { |
598 | entry->valid = 0; |
599 | if (entry == rcu_dereference(netlbl_domhsh_def_ipv4)) |
600 | RCU_INIT_POINTER(netlbl_domhsh_def_ipv4, NULL); |
601 | else if (entry == rcu_dereference(netlbl_domhsh_def_ipv6)) |
602 | RCU_INIT_POINTER(netlbl_domhsh_def_ipv6, NULL); |
603 | else |
604 | list_del_rcu(entry: &entry->list); |
605 | } else |
606 | ret_val = -ENOENT; |
607 | spin_unlock(lock: &netlbl_domhsh_lock); |
608 | |
609 | if (ret_val) |
610 | return ret_val; |
611 | |
612 | audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info); |
613 | if (audit_buf != NULL) { |
614 | audit_log_format(ab: audit_buf, |
615 | fmt: " nlbl_domain=%s res=1" , |
616 | entry->domain ? entry->domain : "(default)" ); |
617 | audit_log_end(ab: audit_buf); |
618 | } |
619 | |
620 | switch (entry->def.type) { |
621 | case NETLBL_NLTYPE_ADDRSELECT: |
622 | netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) { |
623 | map4 = netlbl_domhsh_addr4_entry(iter4); |
624 | cipso_v4_doi_putdef(doi_def: map4->def.cipso); |
625 | } |
626 | #if IS_ENABLED(CONFIG_IPV6) |
627 | netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) { |
628 | map6 = netlbl_domhsh_addr6_entry(iter6); |
629 | calipso_doi_putdef(doi_def: map6->def.calipso); |
630 | } |
631 | #endif /* IPv6 */ |
632 | break; |
633 | case NETLBL_NLTYPE_CIPSOV4: |
634 | cipso_v4_doi_putdef(doi_def: entry->def.cipso); |
635 | break; |
636 | #if IS_ENABLED(CONFIG_IPV6) |
637 | case NETLBL_NLTYPE_CALIPSO: |
638 | calipso_doi_putdef(doi_def: entry->def.calipso); |
639 | break; |
640 | #endif /* IPv6 */ |
641 | } |
642 | call_rcu(head: &entry->rcu, func: netlbl_domhsh_free_entry); |
643 | |
644 | return ret_val; |
645 | } |
646 | |
647 | /** |
648 | * netlbl_domhsh_remove_af4 - Removes an address selector entry |
649 | * @domain: the domain |
650 | * @addr: IPv4 address |
651 | * @mask: IPv4 address mask |
652 | * @audit_info: NetLabel audit information |
653 | * |
654 | * Description: |
655 | * Removes an individual address selector from a domain mapping and potentially |
656 | * the entire mapping if it is empty. Returns zero on success, negative values |
657 | * on failure. |
658 | * |
659 | */ |
660 | int netlbl_domhsh_remove_af4(const char *domain, |
661 | const struct in_addr *addr, |
662 | const struct in_addr *mask, |
663 | struct netlbl_audit *audit_info) |
664 | { |
665 | struct netlbl_dom_map *entry_map; |
666 | struct netlbl_af4list *entry_addr; |
667 | struct netlbl_af4list *iter4; |
668 | #if IS_ENABLED(CONFIG_IPV6) |
669 | struct netlbl_af6list *iter6; |
670 | #endif /* IPv6 */ |
671 | struct netlbl_domaddr4_map *entry; |
672 | |
673 | rcu_read_lock(); |
674 | |
675 | if (domain) |
676 | entry_map = netlbl_domhsh_search(domain, AF_INET); |
677 | else |
678 | entry_map = netlbl_domhsh_search_def(domain, AF_INET); |
679 | if (entry_map == NULL || |
680 | entry_map->def.type != NETLBL_NLTYPE_ADDRSELECT) |
681 | goto remove_af4_failure; |
682 | |
683 | spin_lock(lock: &netlbl_domhsh_lock); |
684 | entry_addr = netlbl_af4list_remove(addr: addr->s_addr, mask: mask->s_addr, |
685 | head: &entry_map->def.addrsel->list4); |
686 | spin_unlock(lock: &netlbl_domhsh_lock); |
687 | |
688 | if (entry_addr == NULL) |
689 | goto remove_af4_failure; |
690 | netlbl_af4list_foreach_rcu(iter4, &entry_map->def.addrsel->list4) |
691 | goto remove_af4_single_addr; |
692 | #if IS_ENABLED(CONFIG_IPV6) |
693 | netlbl_af6list_foreach_rcu(iter6, &entry_map->def.addrsel->list6) |
694 | goto remove_af4_single_addr; |
695 | #endif /* IPv6 */ |
696 | /* the domain mapping is empty so remove it from the mapping table */ |
697 | netlbl_domhsh_remove_entry(entry: entry_map, audit_info); |
698 | |
699 | remove_af4_single_addr: |
700 | rcu_read_unlock(); |
701 | /* yick, we can't use call_rcu here because we don't have a rcu head |
702 | * pointer but hopefully this should be a rare case so the pause |
703 | * shouldn't be a problem */ |
704 | synchronize_rcu(); |
705 | entry = netlbl_domhsh_addr4_entry(entry_addr); |
706 | cipso_v4_doi_putdef(doi_def: entry->def.cipso); |
707 | kfree(objp: entry); |
708 | return 0; |
709 | |
710 | remove_af4_failure: |
711 | rcu_read_unlock(); |
712 | return -ENOENT; |
713 | } |
714 | |
715 | #if IS_ENABLED(CONFIG_IPV6) |
716 | /** |
717 | * netlbl_domhsh_remove_af6 - Removes an address selector entry |
718 | * @domain: the domain |
719 | * @addr: IPv6 address |
720 | * @mask: IPv6 address mask |
721 | * @audit_info: NetLabel audit information |
722 | * |
723 | * Description: |
724 | * Removes an individual address selector from a domain mapping and potentially |
725 | * the entire mapping if it is empty. Returns zero on success, negative values |
726 | * on failure. |
727 | * |
728 | */ |
729 | int netlbl_domhsh_remove_af6(const char *domain, |
730 | const struct in6_addr *addr, |
731 | const struct in6_addr *mask, |
732 | struct netlbl_audit *audit_info) |
733 | { |
734 | struct netlbl_dom_map *entry_map; |
735 | struct netlbl_af6list *entry_addr; |
736 | struct netlbl_af4list *iter4; |
737 | struct netlbl_af6list *iter6; |
738 | struct netlbl_domaddr6_map *entry; |
739 | |
740 | rcu_read_lock(); |
741 | |
742 | if (domain) |
743 | entry_map = netlbl_domhsh_search(domain, AF_INET6); |
744 | else |
745 | entry_map = netlbl_domhsh_search_def(domain, AF_INET6); |
746 | if (entry_map == NULL || |
747 | entry_map->def.type != NETLBL_NLTYPE_ADDRSELECT) |
748 | goto remove_af6_failure; |
749 | |
750 | spin_lock(lock: &netlbl_domhsh_lock); |
751 | entry_addr = netlbl_af6list_remove(addr, mask, |
752 | head: &entry_map->def.addrsel->list6); |
753 | spin_unlock(lock: &netlbl_domhsh_lock); |
754 | |
755 | if (entry_addr == NULL) |
756 | goto remove_af6_failure; |
757 | netlbl_af4list_foreach_rcu(iter4, &entry_map->def.addrsel->list4) |
758 | goto remove_af6_single_addr; |
759 | netlbl_af6list_foreach_rcu(iter6, &entry_map->def.addrsel->list6) |
760 | goto remove_af6_single_addr; |
761 | /* the domain mapping is empty so remove it from the mapping table */ |
762 | netlbl_domhsh_remove_entry(entry: entry_map, audit_info); |
763 | |
764 | remove_af6_single_addr: |
765 | rcu_read_unlock(); |
766 | /* yick, we can't use call_rcu here because we don't have a rcu head |
767 | * pointer but hopefully this should be a rare case so the pause |
768 | * shouldn't be a problem */ |
769 | synchronize_rcu(); |
770 | entry = netlbl_domhsh_addr6_entry(entry_addr); |
771 | calipso_doi_putdef(doi_def: entry->def.calipso); |
772 | kfree(objp: entry); |
773 | return 0; |
774 | |
775 | remove_af6_failure: |
776 | rcu_read_unlock(); |
777 | return -ENOENT; |
778 | } |
779 | #endif /* IPv6 */ |
780 | |
781 | /** |
782 | * netlbl_domhsh_remove - Removes an entry from the domain hash table |
783 | * @domain: the domain to remove |
784 | * @family: address family |
785 | * @audit_info: NetLabel audit information |
786 | * |
787 | * Description: |
788 | * Removes an entry from the domain hash table and handles any updates to the |
789 | * lower level protocol handler (i.e. CIPSO). @family may be %AF_UNSPEC which |
790 | * removes all address family entries. Returns zero on success, negative on |
791 | * failure. |
792 | * |
793 | */ |
794 | int netlbl_domhsh_remove(const char *domain, u16 family, |
795 | struct netlbl_audit *audit_info) |
796 | { |
797 | int ret_val = -EINVAL; |
798 | struct netlbl_dom_map *entry; |
799 | |
800 | rcu_read_lock(); |
801 | |
802 | if (family == AF_INET || family == AF_UNSPEC) { |
803 | if (domain) |
804 | entry = netlbl_domhsh_search(domain, AF_INET); |
805 | else |
806 | entry = netlbl_domhsh_search_def(domain, AF_INET); |
807 | ret_val = netlbl_domhsh_remove_entry(entry, audit_info); |
808 | if (ret_val && ret_val != -ENOENT) |
809 | goto done; |
810 | } |
811 | if (family == AF_INET6 || family == AF_UNSPEC) { |
812 | int ret_val2; |
813 | |
814 | if (domain) |
815 | entry = netlbl_domhsh_search(domain, AF_INET6); |
816 | else |
817 | entry = netlbl_domhsh_search_def(domain, AF_INET6); |
818 | ret_val2 = netlbl_domhsh_remove_entry(entry, audit_info); |
819 | if (ret_val2 != -ENOENT) |
820 | ret_val = ret_val2; |
821 | } |
822 | done: |
823 | rcu_read_unlock(); |
824 | |
825 | return ret_val; |
826 | } |
827 | |
828 | /** |
829 | * netlbl_domhsh_remove_default - Removes the default entry from the table |
830 | * @family: address family |
831 | * @audit_info: NetLabel audit information |
832 | * |
833 | * Description: |
834 | * Removes/resets the default entry corresponding to @family from the domain |
835 | * hash table and handles any updates to the lower level protocol handler |
836 | * (i.e. CIPSO). @family may be %AF_UNSPEC which removes all address family |
837 | * entries. Returns zero on success, negative on failure. |
838 | * |
839 | */ |
840 | int netlbl_domhsh_remove_default(u16 family, struct netlbl_audit *audit_info) |
841 | { |
842 | return netlbl_domhsh_remove(NULL, family, audit_info); |
843 | } |
844 | |
845 | /** |
846 | * netlbl_domhsh_getentry - Get an entry from the domain hash table |
847 | * @domain: the domain name to search for |
848 | * @family: address family |
849 | * |
850 | * Description: |
851 | * Look through the domain hash table searching for an entry to match @domain, |
852 | * with address family @family, return a pointer to a copy of the entry or |
853 | * NULL. The caller is responsible for ensuring that rcu_read_[un]lock() is |
854 | * called. |
855 | * |
856 | */ |
857 | struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain, u16 family) |
858 | { |
859 | if (family == AF_UNSPEC) |
860 | return NULL; |
861 | return netlbl_domhsh_search_def(domain, family); |
862 | } |
863 | |
864 | /** |
865 | * netlbl_domhsh_getentry_af4 - Get an entry from the domain hash table |
866 | * @domain: the domain name to search for |
867 | * @addr: the IP address to search for |
868 | * |
869 | * Description: |
870 | * Look through the domain hash table searching for an entry to match @domain |
871 | * and @addr, return a pointer to a copy of the entry or NULL. The caller is |
872 | * responsible for ensuring that rcu_read_[un]lock() is called. |
873 | * |
874 | */ |
875 | struct netlbl_dommap_def *netlbl_domhsh_getentry_af4(const char *domain, |
876 | __be32 addr) |
877 | { |
878 | struct netlbl_dom_map *dom_iter; |
879 | struct netlbl_af4list *addr_iter; |
880 | |
881 | dom_iter = netlbl_domhsh_search_def(domain, AF_INET); |
882 | if (dom_iter == NULL) |
883 | return NULL; |
884 | |
885 | if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT) |
886 | return &dom_iter->def; |
887 | addr_iter = netlbl_af4list_search(addr, head: &dom_iter->def.addrsel->list4); |
888 | if (addr_iter == NULL) |
889 | return NULL; |
890 | return &(netlbl_domhsh_addr4_entry(addr_iter)->def); |
891 | } |
892 | |
893 | #if IS_ENABLED(CONFIG_IPV6) |
894 | /** |
895 | * netlbl_domhsh_getentry_af6 - Get an entry from the domain hash table |
896 | * @domain: the domain name to search for |
897 | * @addr: the IP address to search for |
898 | * |
899 | * Description: |
900 | * Look through the domain hash table searching for an entry to match @domain |
901 | * and @addr, return a pointer to a copy of the entry or NULL. The caller is |
902 | * responsible for ensuring that rcu_read_[un]lock() is called. |
903 | * |
904 | */ |
905 | struct netlbl_dommap_def *netlbl_domhsh_getentry_af6(const char *domain, |
906 | const struct in6_addr *addr) |
907 | { |
908 | struct netlbl_dom_map *dom_iter; |
909 | struct netlbl_af6list *addr_iter; |
910 | |
911 | dom_iter = netlbl_domhsh_search_def(domain, AF_INET6); |
912 | if (dom_iter == NULL) |
913 | return NULL; |
914 | |
915 | if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT) |
916 | return &dom_iter->def; |
917 | addr_iter = netlbl_af6list_search(addr, head: &dom_iter->def.addrsel->list6); |
918 | if (addr_iter == NULL) |
919 | return NULL; |
920 | return &(netlbl_domhsh_addr6_entry(addr_iter)->def); |
921 | } |
922 | #endif /* IPv6 */ |
923 | |
924 | /** |
925 | * netlbl_domhsh_walk - Iterate through the domain mapping hash table |
926 | * @skip_bkt: the number of buckets to skip at the start |
927 | * @skip_chain: the number of entries to skip in the first iterated bucket |
928 | * @callback: callback for each entry |
929 | * @cb_arg: argument for the callback function |
930 | * |
931 | * Description: |
932 | * Iterate over the domain mapping hash table, skipping the first @skip_bkt |
933 | * buckets and @skip_chain entries. For each entry in the table call |
934 | * @callback, if @callback returns a negative value stop 'walking' through the |
935 | * table and return. Updates the values in @skip_bkt and @skip_chain on |
936 | * return. Returns zero on success, negative values on failure. |
937 | * |
938 | */ |
939 | int netlbl_domhsh_walk(u32 *skip_bkt, |
940 | u32 *skip_chain, |
941 | int (*callback) (struct netlbl_dom_map *entry, void *arg), |
942 | void *cb_arg) |
943 | { |
944 | int ret_val = -ENOENT; |
945 | u32 iter_bkt; |
946 | struct list_head *iter_list; |
947 | struct netlbl_dom_map *iter_entry; |
948 | u32 chain_cnt = 0; |
949 | |
950 | rcu_read_lock(); |
951 | for (iter_bkt = *skip_bkt; |
952 | iter_bkt < rcu_dereference(netlbl_domhsh)->size; |
953 | iter_bkt++, chain_cnt = 0) { |
954 | iter_list = &rcu_dereference(netlbl_domhsh)->tbl[iter_bkt]; |
955 | list_for_each_entry_rcu(iter_entry, iter_list, list) |
956 | if (iter_entry->valid) { |
957 | if (chain_cnt++ < *skip_chain) |
958 | continue; |
959 | ret_val = callback(iter_entry, cb_arg); |
960 | if (ret_val < 0) { |
961 | chain_cnt--; |
962 | goto walk_return; |
963 | } |
964 | } |
965 | } |
966 | |
967 | walk_return: |
968 | rcu_read_unlock(); |
969 | *skip_bkt = iter_bkt; |
970 | *skip_chain = chain_cnt; |
971 | return ret_val; |
972 | } |
973 | |