1 /*
2 * NetLabel Unlabeled Support
3 *
4 * This file defines functions for dealing with unlabeled packets for the
5 * NetLabel system. The NetLabel system manages static and dynamic label
6 * mappings for network protocols such 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/types.h>
31 #include <linux/rcupdate.h>
32 #include <linux/list.h>
33 #include <linux/spinlock.h>
34 #include <linux/socket.h>
35 #include <linux/string.h>
36 #include <linux/skbuff.h>
37 #include <linux/audit.h>
38 #include <linux/in.h>
39 #include <linux/in6.h>
40 #include <linux/ip.h>
41 #include <linux/ipv6.h>
42 #include <linux/notifier.h>
43 #include <linux/netdevice.h>
44 #include <linux/security.h>
45 #include <linux/slab.h>
46 #include <net/sock.h>
47 #include <net/netlink.h>
48 #include <net/genetlink.h>
49 #include <net/ip.h>
50 #include <net/ipv6.h>
51 #include <net/net_namespace.h>
52 #include <net/netlabel.h>
53 #include <asm/bug.h>
54 #include <linux/atomic.h>
55
56 #include "netlabel_user.h"
57 #include "netlabel_addrlist.h"
58 #include "netlabel_domainhash.h"
59 #include "netlabel_unlabeled.h"
60 #include "netlabel_mgmt.h"
61
62 /* NOTE: at present we always use init's network namespace since we don't
63 * presently support different namespaces even though the majority of
64 * the functions in this file are "namespace safe" */
65
66 /* The unlabeled connection hash table which we use to map network interfaces
67 * and addresses of unlabeled packets to a user specified secid value for the
68 * LSM. The hash table is used to lookup the network interface entry
69 * (struct netlbl_unlhsh_iface) and then the interface entry is used to
70 * lookup an IP address match from an ordered list. If a network interface
71 * match can not be found in the hash table then the default entry
72 * (netlbl_unlhsh_def) is used. The IP address entry list
73 * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
74 * larger netmask come first.
75 */
76 struct netlbl_unlhsh_tbl {
77 struct list_head *tbl;
78 u32 size;
79 };
80 #define netlbl_unlhsh_addr4_entry(iter) \
81 container_of(iter, struct netlbl_unlhsh_addr4, list)
82 struct netlbl_unlhsh_addr4 {
83 u32 secid;
84
85 struct netlbl_af4list list;
86 struct rcu_head rcu;
87 };
88 #define netlbl_unlhsh_addr6_entry(iter) \
89 container_of(iter, struct netlbl_unlhsh_addr6, list)
90 struct netlbl_unlhsh_addr6 {
91 u32 secid;
92
93 struct netlbl_af6list list;
94 struct rcu_head rcu;
95 };
96 struct netlbl_unlhsh_iface {
97 int ifindex;
98 struct list_head addr4_list;
99 struct list_head addr6_list;
100
101 u32 valid;
102 struct list_head list;
103 struct rcu_head rcu;
104 };
105
106 /* Argument struct for netlbl_unlhsh_walk() */
107 struct netlbl_unlhsh_walk_arg {
108 struct netlink_callback *nl_cb;
109 struct sk_buff *skb;
110 u32 seq;
111 };
112
113 /* Unlabeled connection hash table */
114 /* updates should be so rare that having one spinlock for the entire
115 * hash table should be okay */
116 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
117 #define netlbl_unlhsh_rcu_deref(p) \
118 rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock))
119 static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL;
120 static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL;
121
122 /* Accept unlabeled packets flag */
123 static u8 netlabel_unlabel_acceptflg = 0;
124
125 /* NetLabel Generic NETLINK unlabeled family */
126 static struct genl_family netlbl_unlabel_gnl_family = {
127 .id = GENL_ID_GENERATE,
128 .hdrsize = 0,
129 .name = NETLBL_NLTYPE_UNLABELED_NAME,
130 .version = NETLBL_PROTO_VERSION,
131 .maxattr = NLBL_UNLABEL_A_MAX,
132 };
133
134 /* NetLabel Netlink attribute policy */
135 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
136 [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
137 [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
138 .len = sizeof(struct in6_addr) },
139 [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
140 .len = sizeof(struct in6_addr) },
141 [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
142 .len = sizeof(struct in_addr) },
143 [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
144 .len = sizeof(struct in_addr) },
145 [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
146 .len = IFNAMSIZ - 1 },
147 [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
148 };
149
150 /*
151 * Unlabeled Connection Hash Table Functions
152 */
153
154 /**
155 * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
156 * @entry: the entry's RCU field
157 *
158 * Description:
159 * This function is designed to be used as a callback to the call_rcu()
160 * function so that memory allocated to a hash table interface entry can be
161 * released safely. It is important to note that this function does not free
162 * the IPv4 and IPv6 address lists contained as part of an interface entry. It
163 * is up to the rest of the code to make sure an interface entry is only freed
164 * once it's address lists are empty.
165 *
166 */
netlbl_unlhsh_free_iface(struct rcu_head * entry)167 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
168 {
169 struct netlbl_unlhsh_iface *iface;
170 struct netlbl_af4list *iter4;
171 struct netlbl_af4list *tmp4;
172 #if IS_ENABLED(CONFIG_IPV6)
173 struct netlbl_af6list *iter6;
174 struct netlbl_af6list *tmp6;
175 #endif /* IPv6 */
176
177 iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
178
179 /* no need for locks here since we are the only one with access to this
180 * structure */
181
182 netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
183 netlbl_af4list_remove_entry(iter4);
184 kfree(netlbl_unlhsh_addr4_entry(iter4));
185 }
186 #if IS_ENABLED(CONFIG_IPV6)
187 netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
188 netlbl_af6list_remove_entry(iter6);
189 kfree(netlbl_unlhsh_addr6_entry(iter6));
190 }
191 #endif /* IPv6 */
192 kfree(iface);
193 }
194
195 /**
196 * netlbl_unlhsh_hash - Hashing function for the hash table
197 * @ifindex: the network interface/device to hash
198 *
199 * Description:
200 * This is the hashing function for the unlabeled hash table, it returns the
201 * bucket number for the given device/interface. The caller is responsible for
202 * ensuring that the hash table is protected with either a RCU read lock or
203 * the hash table lock.
204 *
205 */
netlbl_unlhsh_hash(int ifindex)206 static u32 netlbl_unlhsh_hash(int ifindex)
207 {
208 return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1);
209 }
210
211 /**
212 * netlbl_unlhsh_search_iface - Search for a matching interface entry
213 * @ifindex: the network interface
214 *
215 * Description:
216 * Searches the unlabeled connection hash table and returns a pointer to the
217 * interface entry which matches @ifindex, otherwise NULL is returned. The
218 * caller is responsible for ensuring that the hash table is protected with
219 * either a RCU read lock or the hash table lock.
220 *
221 */
netlbl_unlhsh_search_iface(int ifindex)222 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
223 {
224 u32 bkt;
225 struct list_head *bkt_list;
226 struct netlbl_unlhsh_iface *iter;
227
228 bkt = netlbl_unlhsh_hash(ifindex);
229 bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt];
230 list_for_each_entry_rcu(iter, bkt_list, list)
231 if (iter->valid && iter->ifindex == ifindex)
232 return iter;
233
234 return NULL;
235 }
236
237 /**
238 * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
239 * @iface: the associated interface entry
240 * @addr: IPv4 address in network byte order
241 * @mask: IPv4 address mask in network byte order
242 * @secid: LSM secid value for entry
243 *
244 * Description:
245 * Add a new address entry into the unlabeled connection hash table using the
246 * interface entry specified by @iface. On success zero is returned, otherwise
247 * a negative value is returned.
248 *
249 */
netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface * iface,const struct in_addr * addr,const struct in_addr * mask,u32 secid)250 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
251 const struct in_addr *addr,
252 const struct in_addr *mask,
253 u32 secid)
254 {
255 int ret_val;
256 struct netlbl_unlhsh_addr4 *entry;
257
258 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
259 if (entry == NULL)
260 return -ENOMEM;
261
262 entry->list.addr = addr->s_addr & mask->s_addr;
263 entry->list.mask = mask->s_addr;
264 entry->list.valid = 1;
265 entry->secid = secid;
266
267 spin_lock(&netlbl_unlhsh_lock);
268 ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
269 spin_unlock(&netlbl_unlhsh_lock);
270
271 if (ret_val != 0)
272 kfree(entry);
273 return ret_val;
274 }
275
276 #if IS_ENABLED(CONFIG_IPV6)
277 /**
278 * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
279 * @iface: the associated interface entry
280 * @addr: IPv6 address in network byte order
281 * @mask: IPv6 address mask in network byte order
282 * @secid: LSM secid value for entry
283 *
284 * Description:
285 * Add a new address entry into the unlabeled connection hash table using the
286 * interface entry specified by @iface. On success zero is returned, otherwise
287 * a negative value is returned.
288 *
289 */
netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface * iface,const struct in6_addr * addr,const struct in6_addr * mask,u32 secid)290 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
291 const struct in6_addr *addr,
292 const struct in6_addr *mask,
293 u32 secid)
294 {
295 int ret_val;
296 struct netlbl_unlhsh_addr6 *entry;
297
298 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
299 if (entry == NULL)
300 return -ENOMEM;
301
302 entry->list.addr = *addr;
303 entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
304 entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
305 entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
306 entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
307 entry->list.mask = *mask;
308 entry->list.valid = 1;
309 entry->secid = secid;
310
311 spin_lock(&netlbl_unlhsh_lock);
312 ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
313 spin_unlock(&netlbl_unlhsh_lock);
314
315 if (ret_val != 0)
316 kfree(entry);
317 return 0;
318 }
319 #endif /* IPv6 */
320
321 /**
322 * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
323 * @ifindex: network interface
324 *
325 * Description:
326 * Add a new, empty, interface entry into the unlabeled connection hash table.
327 * On success a pointer to the new interface entry is returned, on failure NULL
328 * is returned.
329 *
330 */
netlbl_unlhsh_add_iface(int ifindex)331 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
332 {
333 u32 bkt;
334 struct netlbl_unlhsh_iface *iface;
335
336 iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
337 if (iface == NULL)
338 return NULL;
339
340 iface->ifindex = ifindex;
341 INIT_LIST_HEAD(&iface->addr4_list);
342 INIT_LIST_HEAD(&iface->addr6_list);
343 iface->valid = 1;
344
345 spin_lock(&netlbl_unlhsh_lock);
346 if (ifindex > 0) {
347 bkt = netlbl_unlhsh_hash(ifindex);
348 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
349 goto add_iface_failure;
350 list_add_tail_rcu(&iface->list,
351 &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]);
352 } else {
353 INIT_LIST_HEAD(&iface->list);
354 if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL)
355 goto add_iface_failure;
356 rcu_assign_pointer(netlbl_unlhsh_def, iface);
357 }
358 spin_unlock(&netlbl_unlhsh_lock);
359
360 return iface;
361
362 add_iface_failure:
363 spin_unlock(&netlbl_unlhsh_lock);
364 kfree(iface);
365 return NULL;
366 }
367
368 /**
369 * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
370 * @net: network namespace
371 * @dev_name: interface name
372 * @addr: IP address in network byte order
373 * @mask: address mask in network byte order
374 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
375 * @secid: LSM secid value for the entry
376 * @audit_info: NetLabel audit information
377 *
378 * Description:
379 * Adds a new entry to the unlabeled connection hash table. Returns zero on
380 * success, negative values on failure.
381 *
382 */
netlbl_unlhsh_add(struct net * net,const char * dev_name,const void * addr,const void * mask,u32 addr_len,u32 secid,struct netlbl_audit * audit_info)383 int netlbl_unlhsh_add(struct net *net,
384 const char *dev_name,
385 const void *addr,
386 const void *mask,
387 u32 addr_len,
388 u32 secid,
389 struct netlbl_audit *audit_info)
390 {
391 int ret_val;
392 int ifindex;
393 struct net_device *dev;
394 struct netlbl_unlhsh_iface *iface;
395 struct audit_buffer *audit_buf = NULL;
396 char *secctx = NULL;
397 u32 secctx_len;
398
399 if (addr_len != sizeof(struct in_addr) &&
400 addr_len != sizeof(struct in6_addr))
401 return -EINVAL;
402
403 rcu_read_lock();
404 if (dev_name != NULL) {
405 dev = dev_get_by_name_rcu(net, dev_name);
406 if (dev == NULL) {
407 ret_val = -ENODEV;
408 goto unlhsh_add_return;
409 }
410 ifindex = dev->ifindex;
411 iface = netlbl_unlhsh_search_iface(ifindex);
412 } else {
413 ifindex = 0;
414 iface = rcu_dereference(netlbl_unlhsh_def);
415 }
416 if (iface == NULL) {
417 iface = netlbl_unlhsh_add_iface(ifindex);
418 if (iface == NULL) {
419 ret_val = -ENOMEM;
420 goto unlhsh_add_return;
421 }
422 }
423 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
424 audit_info);
425 switch (addr_len) {
426 case sizeof(struct in_addr): {
427 const struct in_addr *addr4 = addr;
428 const struct in_addr *mask4 = mask;
429
430 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
431 if (audit_buf != NULL)
432 netlbl_af4list_audit_addr(audit_buf, 1,
433 dev_name,
434 addr4->s_addr,
435 mask4->s_addr);
436 break;
437 }
438 #if IS_ENABLED(CONFIG_IPV6)
439 case sizeof(struct in6_addr): {
440 const struct in6_addr *addr6 = addr;
441 const struct in6_addr *mask6 = mask;
442
443 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
444 if (audit_buf != NULL)
445 netlbl_af6list_audit_addr(audit_buf, 1,
446 dev_name,
447 addr6, mask6);
448 break;
449 }
450 #endif /* IPv6 */
451 default:
452 ret_val = -EINVAL;
453 }
454 if (ret_val == 0)
455 atomic_inc(&netlabel_mgmt_protocount);
456
457 unlhsh_add_return:
458 rcu_read_unlock();
459 if (audit_buf != NULL) {
460 if (security_secid_to_secctx(secid,
461 &secctx,
462 &secctx_len) == 0) {
463 audit_log_format(audit_buf, " sec_obj=%s", secctx);
464 security_release_secctx(secctx, secctx_len);
465 }
466 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
467 audit_log_end(audit_buf);
468 }
469 return ret_val;
470 }
471
472 /**
473 * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
474 * @net: network namespace
475 * @iface: interface entry
476 * @addr: IP address
477 * @mask: IP address mask
478 * @audit_info: NetLabel audit information
479 *
480 * Description:
481 * Remove an IP address entry from the unlabeled connection hash table.
482 * Returns zero on success, negative values on failure.
483 *
484 */
netlbl_unlhsh_remove_addr4(struct net * net,struct netlbl_unlhsh_iface * iface,const struct in_addr * addr,const struct in_addr * mask,struct netlbl_audit * audit_info)485 static int netlbl_unlhsh_remove_addr4(struct net *net,
486 struct netlbl_unlhsh_iface *iface,
487 const struct in_addr *addr,
488 const struct in_addr *mask,
489 struct netlbl_audit *audit_info)
490 {
491 struct netlbl_af4list *list_entry;
492 struct netlbl_unlhsh_addr4 *entry;
493 struct audit_buffer *audit_buf;
494 struct net_device *dev;
495 char *secctx;
496 u32 secctx_len;
497
498 spin_lock(&netlbl_unlhsh_lock);
499 list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
500 &iface->addr4_list);
501 spin_unlock(&netlbl_unlhsh_lock);
502 if (list_entry != NULL)
503 entry = netlbl_unlhsh_addr4_entry(list_entry);
504 else
505 entry = NULL;
506
507 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
508 audit_info);
509 if (audit_buf != NULL) {
510 dev = dev_get_by_index(net, iface->ifindex);
511 netlbl_af4list_audit_addr(audit_buf, 1,
512 (dev != NULL ? dev->name : NULL),
513 addr->s_addr, mask->s_addr);
514 if (dev != NULL)
515 dev_put(dev);
516 if (entry != NULL &&
517 security_secid_to_secctx(entry->secid,
518 &secctx, &secctx_len) == 0) {
519 audit_log_format(audit_buf, " sec_obj=%s", secctx);
520 security_release_secctx(secctx, secctx_len);
521 }
522 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
523 audit_log_end(audit_buf);
524 }
525
526 if (entry == NULL)
527 return -ENOENT;
528
529 kfree_rcu(entry, rcu);
530 return 0;
531 }
532
533 #if IS_ENABLED(CONFIG_IPV6)
534 /**
535 * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
536 * @net: network namespace
537 * @iface: interface entry
538 * @addr: IP address
539 * @mask: IP address mask
540 * @audit_info: NetLabel audit information
541 *
542 * Description:
543 * Remove an IP address entry from the unlabeled connection hash table.
544 * Returns zero on success, negative values on failure.
545 *
546 */
netlbl_unlhsh_remove_addr6(struct net * net,struct netlbl_unlhsh_iface * iface,const struct in6_addr * addr,const struct in6_addr * mask,struct netlbl_audit * audit_info)547 static int netlbl_unlhsh_remove_addr6(struct net *net,
548 struct netlbl_unlhsh_iface *iface,
549 const struct in6_addr *addr,
550 const struct in6_addr *mask,
551 struct netlbl_audit *audit_info)
552 {
553 struct netlbl_af6list *list_entry;
554 struct netlbl_unlhsh_addr6 *entry;
555 struct audit_buffer *audit_buf;
556 struct net_device *dev;
557 char *secctx;
558 u32 secctx_len;
559
560 spin_lock(&netlbl_unlhsh_lock);
561 list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
562 spin_unlock(&netlbl_unlhsh_lock);
563 if (list_entry != NULL)
564 entry = netlbl_unlhsh_addr6_entry(list_entry);
565 else
566 entry = NULL;
567
568 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
569 audit_info);
570 if (audit_buf != NULL) {
571 dev = dev_get_by_index(net, iface->ifindex);
572 netlbl_af6list_audit_addr(audit_buf, 1,
573 (dev != NULL ? dev->name : NULL),
574 addr, mask);
575 if (dev != NULL)
576 dev_put(dev);
577 if (entry != NULL &&
578 security_secid_to_secctx(entry->secid,
579 &secctx, &secctx_len) == 0) {
580 audit_log_format(audit_buf, " sec_obj=%s", secctx);
581 security_release_secctx(secctx, secctx_len);
582 }
583 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
584 audit_log_end(audit_buf);
585 }
586
587 if (entry == NULL)
588 return -ENOENT;
589
590 kfree_rcu(entry, rcu);
591 return 0;
592 }
593 #endif /* IPv6 */
594
595 /**
596 * netlbl_unlhsh_condremove_iface - Remove an interface entry
597 * @iface: the interface entry
598 *
599 * Description:
600 * Remove an interface entry from the unlabeled connection hash table if it is
601 * empty. An interface entry is considered to be empty if there are no
602 * address entries assigned to it.
603 *
604 */
netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface * iface)605 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
606 {
607 struct netlbl_af4list *iter4;
608 #if IS_ENABLED(CONFIG_IPV6)
609 struct netlbl_af6list *iter6;
610 #endif /* IPv6 */
611
612 spin_lock(&netlbl_unlhsh_lock);
613 netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
614 goto unlhsh_condremove_failure;
615 #if IS_ENABLED(CONFIG_IPV6)
616 netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
617 goto unlhsh_condremove_failure;
618 #endif /* IPv6 */
619 iface->valid = 0;
620 if (iface->ifindex > 0)
621 list_del_rcu(&iface->list);
622 else
623 RCU_INIT_POINTER(netlbl_unlhsh_def, NULL);
624 spin_unlock(&netlbl_unlhsh_lock);
625
626 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
627 return;
628
629 unlhsh_condremove_failure:
630 spin_unlock(&netlbl_unlhsh_lock);
631 }
632
633 /**
634 * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
635 * @net: network namespace
636 * @dev_name: interface name
637 * @addr: IP address in network byte order
638 * @mask: address mask in network byte order
639 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
640 * @audit_info: NetLabel audit information
641 *
642 * Description:
643 * Removes and existing entry from the unlabeled connection hash table.
644 * Returns zero on success, negative values on failure.
645 *
646 */
netlbl_unlhsh_remove(struct net * net,const char * dev_name,const void * addr,const void * mask,u32 addr_len,struct netlbl_audit * audit_info)647 int netlbl_unlhsh_remove(struct net *net,
648 const char *dev_name,
649 const void *addr,
650 const void *mask,
651 u32 addr_len,
652 struct netlbl_audit *audit_info)
653 {
654 int ret_val;
655 struct net_device *dev;
656 struct netlbl_unlhsh_iface *iface;
657
658 if (addr_len != sizeof(struct in_addr) &&
659 addr_len != sizeof(struct in6_addr))
660 return -EINVAL;
661
662 rcu_read_lock();
663 if (dev_name != NULL) {
664 dev = dev_get_by_name_rcu(net, dev_name);
665 if (dev == NULL) {
666 ret_val = -ENODEV;
667 goto unlhsh_remove_return;
668 }
669 iface = netlbl_unlhsh_search_iface(dev->ifindex);
670 } else
671 iface = rcu_dereference(netlbl_unlhsh_def);
672 if (iface == NULL) {
673 ret_val = -ENOENT;
674 goto unlhsh_remove_return;
675 }
676 switch (addr_len) {
677 case sizeof(struct in_addr):
678 ret_val = netlbl_unlhsh_remove_addr4(net,
679 iface, addr, mask,
680 audit_info);
681 break;
682 #if IS_ENABLED(CONFIG_IPV6)
683 case sizeof(struct in6_addr):
684 ret_val = netlbl_unlhsh_remove_addr6(net,
685 iface, addr, mask,
686 audit_info);
687 break;
688 #endif /* IPv6 */
689 default:
690 ret_val = -EINVAL;
691 }
692 if (ret_val == 0) {
693 netlbl_unlhsh_condremove_iface(iface);
694 atomic_dec(&netlabel_mgmt_protocount);
695 }
696
697 unlhsh_remove_return:
698 rcu_read_unlock();
699 return ret_val;
700 }
701
702 /*
703 * General Helper Functions
704 */
705
706 /**
707 * netlbl_unlhsh_netdev_handler - Network device notification handler
708 * @this: notifier block
709 * @event: the event
710 * @ptr: the netdevice notifier info (cast to void)
711 *
712 * Description:
713 * Handle network device events, although at present all we care about is a
714 * network device going away. In the case of a device going away we clear any
715 * related entries from the unlabeled connection hash table.
716 *
717 */
netlbl_unlhsh_netdev_handler(struct notifier_block * this,unsigned long event,void * ptr)718 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
719 unsigned long event, void *ptr)
720 {
721 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
722 struct netlbl_unlhsh_iface *iface = NULL;
723
724 if (!net_eq(dev_net(dev), &init_net))
725 return NOTIFY_DONE;
726
727 /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
728 if (event == NETDEV_DOWN) {
729 spin_lock(&netlbl_unlhsh_lock);
730 iface = netlbl_unlhsh_search_iface(dev->ifindex);
731 if (iface != NULL && iface->valid) {
732 iface->valid = 0;
733 list_del_rcu(&iface->list);
734 } else
735 iface = NULL;
736 spin_unlock(&netlbl_unlhsh_lock);
737 }
738
739 if (iface != NULL)
740 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
741
742 return NOTIFY_DONE;
743 }
744
745 /**
746 * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
747 * @value: desired value
748 * @audit_info: NetLabel audit information
749 *
750 * Description:
751 * Set the value of the unlabeled accept flag to @value.
752 *
753 */
netlbl_unlabel_acceptflg_set(u8 value,struct netlbl_audit * audit_info)754 static void netlbl_unlabel_acceptflg_set(u8 value,
755 struct netlbl_audit *audit_info)
756 {
757 struct audit_buffer *audit_buf;
758 u8 old_val;
759
760 old_val = netlabel_unlabel_acceptflg;
761 netlabel_unlabel_acceptflg = value;
762 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
763 audit_info);
764 if (audit_buf != NULL) {
765 audit_log_format(audit_buf,
766 " unlbl_accept=%u old=%u", value, old_val);
767 audit_log_end(audit_buf);
768 }
769 }
770
771 /**
772 * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
773 * @info: the Generic NETLINK info block
774 * @addr: the IP address
775 * @mask: the IP address mask
776 * @len: the address length
777 *
778 * Description:
779 * Examine the Generic NETLINK message and extract the IP address information.
780 * Returns zero on success, negative values on failure.
781 *
782 */
netlbl_unlabel_addrinfo_get(struct genl_info * info,void ** addr,void ** mask,u32 * len)783 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
784 void **addr,
785 void **mask,
786 u32 *len)
787 {
788 u32 addr_len;
789
790 if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
791 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
792 if (addr_len != sizeof(struct in_addr) &&
793 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
794 return -EINVAL;
795 *len = addr_len;
796 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
797 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
798 return 0;
799 } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
800 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
801 if (addr_len != sizeof(struct in6_addr) &&
802 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
803 return -EINVAL;
804 *len = addr_len;
805 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
806 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
807 return 0;
808 }
809
810 return -EINVAL;
811 }
812
813 /*
814 * NetLabel Command Handlers
815 */
816
817 /**
818 * netlbl_unlabel_accept - Handle an ACCEPT message
819 * @skb: the NETLINK buffer
820 * @info: the Generic NETLINK info block
821 *
822 * Description:
823 * Process a user generated ACCEPT message and set the accept flag accordingly.
824 * Returns zero on success, negative values on failure.
825 *
826 */
netlbl_unlabel_accept(struct sk_buff * skb,struct genl_info * info)827 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
828 {
829 u8 value;
830 struct netlbl_audit audit_info;
831
832 if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
833 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
834 if (value == 1 || value == 0) {
835 netlbl_netlink_auditinfo(skb, &audit_info);
836 netlbl_unlabel_acceptflg_set(value, &audit_info);
837 return 0;
838 }
839 }
840
841 return -EINVAL;
842 }
843
844 /**
845 * netlbl_unlabel_list - Handle a LIST message
846 * @skb: the NETLINK buffer
847 * @info: the Generic NETLINK info block
848 *
849 * Description:
850 * Process a user generated LIST message and respond with the current status.
851 * Returns zero on success, negative values on failure.
852 *
853 */
netlbl_unlabel_list(struct sk_buff * skb,struct genl_info * info)854 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
855 {
856 int ret_val = -EINVAL;
857 struct sk_buff *ans_skb;
858 void *data;
859
860 ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
861 if (ans_skb == NULL)
862 goto list_failure;
863 data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
864 0, NLBL_UNLABEL_C_LIST);
865 if (data == NULL) {
866 ret_val = -ENOMEM;
867 goto list_failure;
868 }
869
870 ret_val = nla_put_u8(ans_skb,
871 NLBL_UNLABEL_A_ACPTFLG,
872 netlabel_unlabel_acceptflg);
873 if (ret_val != 0)
874 goto list_failure;
875
876 genlmsg_end(ans_skb, data);
877 return genlmsg_reply(ans_skb, info);
878
879 list_failure:
880 kfree_skb(ans_skb);
881 return ret_val;
882 }
883
884 /**
885 * netlbl_unlabel_staticadd - Handle a STATICADD message
886 * @skb: the NETLINK buffer
887 * @info: the Generic NETLINK info block
888 *
889 * Description:
890 * Process a user generated STATICADD message and add a new unlabeled
891 * connection entry to the hash table. Returns zero on success, negative
892 * values on failure.
893 *
894 */
netlbl_unlabel_staticadd(struct sk_buff * skb,struct genl_info * info)895 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
896 struct genl_info *info)
897 {
898 int ret_val;
899 char *dev_name;
900 void *addr;
901 void *mask;
902 u32 addr_len;
903 u32 secid;
904 struct netlbl_audit audit_info;
905
906 /* Don't allow users to add both IPv4 and IPv6 addresses for a
907 * single entry. However, allow users to create two entries, one each
908 * for IPv4 and IPv4, with the same LSM security context which should
909 * achieve the same result. */
910 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
911 !info->attrs[NLBL_UNLABEL_A_IFACE] ||
912 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
913 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
914 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
915 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
916 return -EINVAL;
917
918 netlbl_netlink_auditinfo(skb, &audit_info);
919
920 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
921 if (ret_val != 0)
922 return ret_val;
923 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
924 ret_val = security_secctx_to_secid(
925 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
926 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
927 &secid);
928 if (ret_val != 0)
929 return ret_val;
930
931 return netlbl_unlhsh_add(&init_net,
932 dev_name, addr, mask, addr_len, secid,
933 &audit_info);
934 }
935
936 /**
937 * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
938 * @skb: the NETLINK buffer
939 * @info: the Generic NETLINK info block
940 *
941 * Description:
942 * Process a user generated STATICADDDEF message and add a new default
943 * unlabeled connection entry. Returns zero on success, negative values on
944 * failure.
945 *
946 */
netlbl_unlabel_staticadddef(struct sk_buff * skb,struct genl_info * info)947 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
948 struct genl_info *info)
949 {
950 int ret_val;
951 void *addr;
952 void *mask;
953 u32 addr_len;
954 u32 secid;
955 struct netlbl_audit audit_info;
956
957 /* Don't allow users to add both IPv4 and IPv6 addresses for a
958 * single entry. However, allow users to create two entries, one each
959 * for IPv4 and IPv6, with the same LSM security context which should
960 * achieve the same result. */
961 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
962 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
963 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
964 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
965 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
966 return -EINVAL;
967
968 netlbl_netlink_auditinfo(skb, &audit_info);
969
970 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
971 if (ret_val != 0)
972 return ret_val;
973 ret_val = security_secctx_to_secid(
974 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
975 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
976 &secid);
977 if (ret_val != 0)
978 return ret_val;
979
980 return netlbl_unlhsh_add(&init_net,
981 NULL, addr, mask, addr_len, secid,
982 &audit_info);
983 }
984
985 /**
986 * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
987 * @skb: the NETLINK buffer
988 * @info: the Generic NETLINK info block
989 *
990 * Description:
991 * Process a user generated STATICREMOVE message and remove the specified
992 * unlabeled connection entry. Returns zero on success, negative values on
993 * failure.
994 *
995 */
netlbl_unlabel_staticremove(struct sk_buff * skb,struct genl_info * info)996 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
997 struct genl_info *info)
998 {
999 int ret_val;
1000 char *dev_name;
1001 void *addr;
1002 void *mask;
1003 u32 addr_len;
1004 struct netlbl_audit audit_info;
1005
1006 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1007 * IPv4 and IPv6 in the same entry. */
1008 if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1009 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1010 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1011 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1012 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1013 return -EINVAL;
1014
1015 netlbl_netlink_auditinfo(skb, &audit_info);
1016
1017 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1018 if (ret_val != 0)
1019 return ret_val;
1020 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1021
1022 return netlbl_unlhsh_remove(&init_net,
1023 dev_name, addr, mask, addr_len,
1024 &audit_info);
1025 }
1026
1027 /**
1028 * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1029 * @skb: the NETLINK buffer
1030 * @info: the Generic NETLINK info block
1031 *
1032 * Description:
1033 * Process a user generated STATICREMOVEDEF message and remove the default
1034 * unlabeled connection entry. Returns zero on success, negative values on
1035 * failure.
1036 *
1037 */
netlbl_unlabel_staticremovedef(struct sk_buff * skb,struct genl_info * info)1038 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1039 struct genl_info *info)
1040 {
1041 int ret_val;
1042 void *addr;
1043 void *mask;
1044 u32 addr_len;
1045 struct netlbl_audit audit_info;
1046
1047 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1048 * IPv4 and IPv6 in the same entry. */
1049 if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1050 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1051 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1052 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1053 return -EINVAL;
1054
1055 netlbl_netlink_auditinfo(skb, &audit_info);
1056
1057 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1058 if (ret_val != 0)
1059 return ret_val;
1060
1061 return netlbl_unlhsh_remove(&init_net,
1062 NULL, addr, mask, addr_len,
1063 &audit_info);
1064 }
1065
1066
1067 /**
1068 * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1069 * @cmd: command/message
1070 * @iface: the interface entry
1071 * @addr4: the IPv4 address entry
1072 * @addr6: the IPv6 address entry
1073 * @arg: the netlbl_unlhsh_walk_arg structure
1074 *
1075 * Description:
1076 * This function is designed to be used to generate a response for a
1077 * STATICLIST or STATICLISTDEF message. When called either @addr4 or @addr6
1078 * can be specified, not both, the other unspecified entry should be set to
1079 * NULL by the caller. Returns the size of the message on success, negative
1080 * values on failure.
1081 *
1082 */
netlbl_unlabel_staticlist_gen(u32 cmd,const struct netlbl_unlhsh_iface * iface,const struct netlbl_unlhsh_addr4 * addr4,const struct netlbl_unlhsh_addr6 * addr6,void * arg)1083 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1084 const struct netlbl_unlhsh_iface *iface,
1085 const struct netlbl_unlhsh_addr4 *addr4,
1086 const struct netlbl_unlhsh_addr6 *addr6,
1087 void *arg)
1088 {
1089 int ret_val = -ENOMEM;
1090 struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1091 struct net_device *dev;
1092 void *data;
1093 u32 secid;
1094 char *secctx;
1095 u32 secctx_len;
1096
1097 data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
1098 cb_arg->seq, &netlbl_unlabel_gnl_family,
1099 NLM_F_MULTI, cmd);
1100 if (data == NULL)
1101 goto list_cb_failure;
1102
1103 if (iface->ifindex > 0) {
1104 dev = dev_get_by_index(&init_net, iface->ifindex);
1105 if (!dev) {
1106 ret_val = -ENODEV;
1107 goto list_cb_failure;
1108 }
1109 ret_val = nla_put_string(cb_arg->skb,
1110 NLBL_UNLABEL_A_IFACE, dev->name);
1111 dev_put(dev);
1112 if (ret_val != 0)
1113 goto list_cb_failure;
1114 }
1115
1116 if (addr4) {
1117 struct in_addr addr_struct;
1118
1119 addr_struct.s_addr = addr4->list.addr;
1120 ret_val = nla_put(cb_arg->skb,
1121 NLBL_UNLABEL_A_IPV4ADDR,
1122 sizeof(struct in_addr),
1123 &addr_struct);
1124 if (ret_val != 0)
1125 goto list_cb_failure;
1126
1127 addr_struct.s_addr = addr4->list.mask;
1128 ret_val = nla_put(cb_arg->skb,
1129 NLBL_UNLABEL_A_IPV4MASK,
1130 sizeof(struct in_addr),
1131 &addr_struct);
1132 if (ret_val != 0)
1133 goto list_cb_failure;
1134
1135 secid = addr4->secid;
1136 } else {
1137 ret_val = nla_put(cb_arg->skb,
1138 NLBL_UNLABEL_A_IPV6ADDR,
1139 sizeof(struct in6_addr),
1140 &addr6->list.addr);
1141 if (ret_val != 0)
1142 goto list_cb_failure;
1143
1144 ret_val = nla_put(cb_arg->skb,
1145 NLBL_UNLABEL_A_IPV6MASK,
1146 sizeof(struct in6_addr),
1147 &addr6->list.mask);
1148 if (ret_val != 0)
1149 goto list_cb_failure;
1150
1151 secid = addr6->secid;
1152 }
1153
1154 ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1155 if (ret_val != 0)
1156 goto list_cb_failure;
1157 ret_val = nla_put(cb_arg->skb,
1158 NLBL_UNLABEL_A_SECCTX,
1159 secctx_len,
1160 secctx);
1161 security_release_secctx(secctx, secctx_len);
1162 if (ret_val != 0)
1163 goto list_cb_failure;
1164
1165 cb_arg->seq++;
1166 return genlmsg_end(cb_arg->skb, data);
1167
1168 list_cb_failure:
1169 genlmsg_cancel(cb_arg->skb, data);
1170 return ret_val;
1171 }
1172
1173 /**
1174 * netlbl_unlabel_staticlist - Handle a STATICLIST message
1175 * @skb: the NETLINK buffer
1176 * @cb: the NETLINK callback
1177 *
1178 * Description:
1179 * Process a user generated STATICLIST message and dump the unlabeled
1180 * connection hash table in a form suitable for use in a kernel generated
1181 * STATICLIST message. Returns the length of @skb.
1182 *
1183 */
netlbl_unlabel_staticlist(struct sk_buff * skb,struct netlink_callback * cb)1184 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1185 struct netlink_callback *cb)
1186 {
1187 struct netlbl_unlhsh_walk_arg cb_arg;
1188 u32 skip_bkt = cb->args[0];
1189 u32 skip_chain = cb->args[1];
1190 u32 iter_bkt;
1191 u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1192 struct netlbl_unlhsh_iface *iface;
1193 struct list_head *iter_list;
1194 struct netlbl_af4list *addr4;
1195 #if IS_ENABLED(CONFIG_IPV6)
1196 struct netlbl_af6list *addr6;
1197 #endif
1198
1199 cb_arg.nl_cb = cb;
1200 cb_arg.skb = skb;
1201 cb_arg.seq = cb->nlh->nlmsg_seq;
1202
1203 rcu_read_lock();
1204 for (iter_bkt = skip_bkt;
1205 iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1206 iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1207 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1208 list_for_each_entry_rcu(iface, iter_list, list) {
1209 if (!iface->valid ||
1210 iter_chain++ < skip_chain)
1211 continue;
1212 netlbl_af4list_foreach_rcu(addr4,
1213 &iface->addr4_list) {
1214 if (iter_addr4++ < cb->args[2])
1215 continue;
1216 if (netlbl_unlabel_staticlist_gen(
1217 NLBL_UNLABEL_C_STATICLIST,
1218 iface,
1219 netlbl_unlhsh_addr4_entry(addr4),
1220 NULL,
1221 &cb_arg) < 0) {
1222 iter_addr4--;
1223 iter_chain--;
1224 goto unlabel_staticlist_return;
1225 }
1226 }
1227 #if IS_ENABLED(CONFIG_IPV6)
1228 netlbl_af6list_foreach_rcu(addr6,
1229 &iface->addr6_list) {
1230 if (iter_addr6++ < cb->args[3])
1231 continue;
1232 if (netlbl_unlabel_staticlist_gen(
1233 NLBL_UNLABEL_C_STATICLIST,
1234 iface,
1235 NULL,
1236 netlbl_unlhsh_addr6_entry(addr6),
1237 &cb_arg) < 0) {
1238 iter_addr6--;
1239 iter_chain--;
1240 goto unlabel_staticlist_return;
1241 }
1242 }
1243 #endif /* IPv6 */
1244 }
1245 }
1246
1247 unlabel_staticlist_return:
1248 rcu_read_unlock();
1249 cb->args[0] = iter_bkt;
1250 cb->args[1] = iter_chain;
1251 cb->args[2] = iter_addr4;
1252 cb->args[3] = iter_addr6;
1253 return skb->len;
1254 }
1255
1256 /**
1257 * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1258 * @skb: the NETLINK buffer
1259 * @cb: the NETLINK callback
1260 *
1261 * Description:
1262 * Process a user generated STATICLISTDEF message and dump the default
1263 * unlabeled connection entry in a form suitable for use in a kernel generated
1264 * STATICLISTDEF message. Returns the length of @skb.
1265 *
1266 */
netlbl_unlabel_staticlistdef(struct sk_buff * skb,struct netlink_callback * cb)1267 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1268 struct netlink_callback *cb)
1269 {
1270 struct netlbl_unlhsh_walk_arg cb_arg;
1271 struct netlbl_unlhsh_iface *iface;
1272 u32 iter_addr4 = 0, iter_addr6 = 0;
1273 struct netlbl_af4list *addr4;
1274 #if IS_ENABLED(CONFIG_IPV6)
1275 struct netlbl_af6list *addr6;
1276 #endif
1277
1278 cb_arg.nl_cb = cb;
1279 cb_arg.skb = skb;
1280 cb_arg.seq = cb->nlh->nlmsg_seq;
1281
1282 rcu_read_lock();
1283 iface = rcu_dereference(netlbl_unlhsh_def);
1284 if (iface == NULL || !iface->valid)
1285 goto unlabel_staticlistdef_return;
1286
1287 netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1288 if (iter_addr4++ < cb->args[0])
1289 continue;
1290 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1291 iface,
1292 netlbl_unlhsh_addr4_entry(addr4),
1293 NULL,
1294 &cb_arg) < 0) {
1295 iter_addr4--;
1296 goto unlabel_staticlistdef_return;
1297 }
1298 }
1299 #if IS_ENABLED(CONFIG_IPV6)
1300 netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1301 if (iter_addr6++ < cb->args[1])
1302 continue;
1303 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1304 iface,
1305 NULL,
1306 netlbl_unlhsh_addr6_entry(addr6),
1307 &cb_arg) < 0) {
1308 iter_addr6--;
1309 goto unlabel_staticlistdef_return;
1310 }
1311 }
1312 #endif /* IPv6 */
1313
1314 unlabel_staticlistdef_return:
1315 rcu_read_unlock();
1316 cb->args[0] = iter_addr4;
1317 cb->args[1] = iter_addr6;
1318 return skb->len;
1319 }
1320
1321 /*
1322 * NetLabel Generic NETLINK Command Definitions
1323 */
1324
1325 static const struct genl_ops netlbl_unlabel_genl_ops[] = {
1326 {
1327 .cmd = NLBL_UNLABEL_C_STATICADD,
1328 .flags = GENL_ADMIN_PERM,
1329 .policy = netlbl_unlabel_genl_policy,
1330 .doit = netlbl_unlabel_staticadd,
1331 .dumpit = NULL,
1332 },
1333 {
1334 .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1335 .flags = GENL_ADMIN_PERM,
1336 .policy = netlbl_unlabel_genl_policy,
1337 .doit = netlbl_unlabel_staticremove,
1338 .dumpit = NULL,
1339 },
1340 {
1341 .cmd = NLBL_UNLABEL_C_STATICLIST,
1342 .flags = 0,
1343 .policy = netlbl_unlabel_genl_policy,
1344 .doit = NULL,
1345 .dumpit = netlbl_unlabel_staticlist,
1346 },
1347 {
1348 .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1349 .flags = GENL_ADMIN_PERM,
1350 .policy = netlbl_unlabel_genl_policy,
1351 .doit = netlbl_unlabel_staticadddef,
1352 .dumpit = NULL,
1353 },
1354 {
1355 .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1356 .flags = GENL_ADMIN_PERM,
1357 .policy = netlbl_unlabel_genl_policy,
1358 .doit = netlbl_unlabel_staticremovedef,
1359 .dumpit = NULL,
1360 },
1361 {
1362 .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1363 .flags = 0,
1364 .policy = netlbl_unlabel_genl_policy,
1365 .doit = NULL,
1366 .dumpit = netlbl_unlabel_staticlistdef,
1367 },
1368 {
1369 .cmd = NLBL_UNLABEL_C_ACCEPT,
1370 .flags = GENL_ADMIN_PERM,
1371 .policy = netlbl_unlabel_genl_policy,
1372 .doit = netlbl_unlabel_accept,
1373 .dumpit = NULL,
1374 },
1375 {
1376 .cmd = NLBL_UNLABEL_C_LIST,
1377 .flags = 0,
1378 .policy = netlbl_unlabel_genl_policy,
1379 .doit = netlbl_unlabel_list,
1380 .dumpit = NULL,
1381 },
1382 };
1383
1384 /*
1385 * NetLabel Generic NETLINK Protocol Functions
1386 */
1387
1388 /**
1389 * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1390 *
1391 * Description:
1392 * Register the unlabeled packet NetLabel component with the Generic NETLINK
1393 * mechanism. Returns zero on success, negative values on failure.
1394 *
1395 */
netlbl_unlabel_genl_init(void)1396 int __init netlbl_unlabel_genl_init(void)
1397 {
1398 return genl_register_family_with_ops(&netlbl_unlabel_gnl_family,
1399 netlbl_unlabel_genl_ops);
1400 }
1401
1402 /*
1403 * NetLabel KAPI Hooks
1404 */
1405
1406 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1407 .notifier_call = netlbl_unlhsh_netdev_handler,
1408 };
1409
1410 /**
1411 * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1412 * @size: the number of bits to use for the hash buckets
1413 *
1414 * Description:
1415 * Initializes the unlabeled connection hash table and registers a network
1416 * device notification handler. This function should only be called by the
1417 * NetLabel subsystem itself during initialization. Returns zero on success,
1418 * non-zero values on error.
1419 *
1420 */
netlbl_unlabel_init(u32 size)1421 int __init netlbl_unlabel_init(u32 size)
1422 {
1423 u32 iter;
1424 struct netlbl_unlhsh_tbl *hsh_tbl;
1425
1426 if (size == 0)
1427 return -EINVAL;
1428
1429 hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1430 if (hsh_tbl == NULL)
1431 return -ENOMEM;
1432 hsh_tbl->size = 1 << size;
1433 hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1434 sizeof(struct list_head),
1435 GFP_KERNEL);
1436 if (hsh_tbl->tbl == NULL) {
1437 kfree(hsh_tbl);
1438 return -ENOMEM;
1439 }
1440 for (iter = 0; iter < hsh_tbl->size; iter++)
1441 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1442
1443 spin_lock(&netlbl_unlhsh_lock);
1444 rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1445 spin_unlock(&netlbl_unlhsh_lock);
1446
1447 register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1448
1449 return 0;
1450 }
1451
1452 /**
1453 * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1454 * @skb: the packet
1455 * @family: protocol family
1456 * @secattr: the security attributes
1457 *
1458 * Description:
1459 * Determine the security attributes, if any, for an unlabled packet and return
1460 * them in @secattr. Returns zero on success and negative values on failure.
1461 *
1462 */
netlbl_unlabel_getattr(const struct sk_buff * skb,u16 family,struct netlbl_lsm_secattr * secattr)1463 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1464 u16 family,
1465 struct netlbl_lsm_secattr *secattr)
1466 {
1467 struct netlbl_unlhsh_iface *iface;
1468
1469 rcu_read_lock();
1470 iface = netlbl_unlhsh_search_iface(skb->skb_iif);
1471 if (iface == NULL)
1472 iface = rcu_dereference(netlbl_unlhsh_def);
1473 if (iface == NULL || !iface->valid)
1474 goto unlabel_getattr_nolabel;
1475 switch (family) {
1476 case PF_INET: {
1477 struct iphdr *hdr4;
1478 struct netlbl_af4list *addr4;
1479
1480 hdr4 = ip_hdr(skb);
1481 addr4 = netlbl_af4list_search(hdr4->saddr,
1482 &iface->addr4_list);
1483 if (addr4 == NULL)
1484 goto unlabel_getattr_nolabel;
1485 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1486 break;
1487 }
1488 #if IS_ENABLED(CONFIG_IPV6)
1489 case PF_INET6: {
1490 struct ipv6hdr *hdr6;
1491 struct netlbl_af6list *addr6;
1492
1493 hdr6 = ipv6_hdr(skb);
1494 addr6 = netlbl_af6list_search(&hdr6->saddr,
1495 &iface->addr6_list);
1496 if (addr6 == NULL)
1497 goto unlabel_getattr_nolabel;
1498 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1499 break;
1500 }
1501 #endif /* IPv6 */
1502 default:
1503 goto unlabel_getattr_nolabel;
1504 }
1505 rcu_read_unlock();
1506
1507 secattr->flags |= NETLBL_SECATTR_SECID;
1508 secattr->type = NETLBL_NLTYPE_UNLABELED;
1509 return 0;
1510
1511 unlabel_getattr_nolabel:
1512 rcu_read_unlock();
1513 if (netlabel_unlabel_acceptflg == 0)
1514 return -ENOMSG;
1515 secattr->type = NETLBL_NLTYPE_UNLABELED;
1516 return 0;
1517 }
1518
1519 /**
1520 * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1521 *
1522 * Description:
1523 * Set the default NetLabel configuration to allow incoming unlabeled packets
1524 * and to send unlabeled network traffic by default.
1525 *
1526 */
netlbl_unlabel_defconf(void)1527 int __init netlbl_unlabel_defconf(void)
1528 {
1529 int ret_val;
1530 struct netlbl_dom_map *entry;
1531 struct netlbl_audit audit_info;
1532
1533 /* Only the kernel is allowed to call this function and the only time
1534 * it is called is at bootup before the audit subsystem is reporting
1535 * messages so don't worry to much about these values. */
1536 security_task_getsecid(current, &audit_info.secid);
1537 audit_info.loginuid = GLOBAL_ROOT_UID;
1538 audit_info.sessionid = 0;
1539
1540 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1541 if (entry == NULL)
1542 return -ENOMEM;
1543 entry->def.type = NETLBL_NLTYPE_UNLABELED;
1544 ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1545 if (ret_val != 0)
1546 return ret_val;
1547
1548 netlbl_unlabel_acceptflg_set(1, &audit_info);
1549
1550 return 0;
1551 }
1552