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, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 *
29 */
30
31 #include <linux/types.h>
32 #include <linux/rcupdate.h>
33 #include <linux/list.h>
34 #include <linux/spinlock.h>
35 #include <linux/socket.h>
36 #include <linux/string.h>
37 #include <linux/skbuff.h>
38 #include <linux/audit.h>
39 #include <linux/in.h>
40 #include <linux/in6.h>
41 #include <linux/ip.h>
42 #include <linux/ipv6.h>
43 #include <linux/notifier.h>
44 #include <linux/netdevice.h>
45 #include <linux/security.h>
46 #include <linux/slab.h>
47 #include <net/sock.h>
48 #include <net/netlink.h>
49 #include <net/genetlink.h>
50 #include <net/ip.h>
51 #include <net/ipv6.h>
52 #include <net/net_namespace.h>
53 #include <net/netlabel.h>
54 #include <asm/bug.h>
55 #include <linux/atomic.h>
56
57 #include "netlabel_user.h"
58 #include "netlabel_addrlist.h"
59 #include "netlabel_domainhash.h"
60 #include "netlabel_unlabeled.h"
61 #include "netlabel_mgmt.h"
62
63 /* NOTE: at present we always use init's network namespace since we don't
64 * presently support different namespaces even though the majority of
65 * the functions in this file are "namespace safe" */
66
67 /* The unlabeled connection hash table which we use to map network interfaces
68 * and addresses of unlabeled packets to a user specified secid value for the
69 * LSM. The hash table is used to lookup the network interface entry
70 * (struct netlbl_unlhsh_iface) and then the interface entry is used to
71 * lookup an IP address match from an ordered list. If a network interface
72 * match can not be found in the hash table then the default entry
73 * (netlbl_unlhsh_def) is used. The IP address entry list
74 * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
75 * larger netmask come first.
76 */
77 struct netlbl_unlhsh_tbl {
78 struct list_head *tbl;
79 u32 size;
80 };
81 #define netlbl_unlhsh_addr4_entry(iter) \
82 container_of(iter, struct netlbl_unlhsh_addr4, list)
83 struct netlbl_unlhsh_addr4 {
84 u32 secid;
85
86 struct netlbl_af4list list;
87 struct rcu_head rcu;
88 };
89 #define netlbl_unlhsh_addr6_entry(iter) \
90 container_of(iter, struct netlbl_unlhsh_addr6, list)
91 struct netlbl_unlhsh_addr6 {
92 u32 secid;
93
94 struct netlbl_af6list list;
95 struct rcu_head rcu;
96 };
97 struct netlbl_unlhsh_iface {
98 int ifindex;
99 struct list_head addr4_list;
100 struct list_head addr6_list;
101
102 u32 valid;
103 struct list_head list;
104 struct rcu_head rcu;
105 };
106
107 /* Argument struct for netlbl_unlhsh_walk() */
108 struct netlbl_unlhsh_walk_arg {
109 struct netlink_callback *nl_cb;
110 struct sk_buff *skb;
111 u32 seq;
112 };
113
114 /* Unlabeled connection hash table */
115 /* updates should be so rare that having one spinlock for the entire
116 * hash table should be okay */
117 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
118 #define netlbl_unlhsh_rcu_deref(p) \
119 rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock))
120 static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL;
121 static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL;
122
123 /* Accept unlabeled packets flag */
124 static u8 netlabel_unlabel_acceptflg = 0;
125
126 /* NetLabel Generic NETLINK unlabeled family */
127 static struct genl_family netlbl_unlabel_gnl_family = {
128 .id = GENL_ID_GENERATE,
129 .hdrsize = 0,
130 .name = NETLBL_NLTYPE_UNLABELED_NAME,
131 .version = NETLBL_PROTO_VERSION,
132 .maxattr = NLBL_UNLABEL_A_MAX,
133 };
134
135 /* NetLabel Netlink attribute policy */
136 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
137 [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
138 [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
139 .len = sizeof(struct in6_addr) },
140 [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
141 .len = sizeof(struct in6_addr) },
142 [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
143 .len = sizeof(struct in_addr) },
144 [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
145 .len = sizeof(struct in_addr) },
146 [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
147 .len = IFNAMSIZ - 1 },
148 [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
149 };
150
151 /*
152 * Unlabeled Connection Hash Table Functions
153 */
154
155 /**
156 * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
157 * @entry: the entry's RCU field
158 *
159 * Description:
160 * This function is designed to be used as a callback to the call_rcu()
161 * function so that memory allocated to a hash table interface entry can be
162 * released safely. It is important to note that this function does not free
163 * the IPv4 and IPv6 address lists contained as part of an interface entry. It
164 * is up to the rest of the code to make sure an interface entry is only freed
165 * once it's address lists are empty.
166 *
167 */
netlbl_unlhsh_free_iface(struct rcu_head * entry)168 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
169 {
170 struct netlbl_unlhsh_iface *iface;
171 struct netlbl_af4list *iter4;
172 struct netlbl_af4list *tmp4;
173 #if IS_ENABLED(CONFIG_IPV6)
174 struct netlbl_af6list *iter6;
175 struct netlbl_af6list *tmp6;
176 #endif /* IPv6 */
177
178 iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
179
180 /* no need for locks here since we are the only one with access to this
181 * structure */
182
183 netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
184 netlbl_af4list_remove_entry(iter4);
185 kfree(netlbl_unlhsh_addr4_entry(iter4));
186 }
187 #if IS_ENABLED(CONFIG_IPV6)
188 netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
189 netlbl_af6list_remove_entry(iter6);
190 kfree(netlbl_unlhsh_addr6_entry(iter6));
191 }
192 #endif /* IPv6 */
193 kfree(iface);
194 }
195
196 /**
197 * netlbl_unlhsh_hash - Hashing function for the hash table
198 * @ifindex: the network interface/device to hash
199 *
200 * Description:
201 * This is the hashing function for the unlabeled hash table, it returns the
202 * bucket number for the given device/interface. The caller is responsible for
203 * ensuring that the hash table is protected with either a RCU read lock or
204 * the hash table lock.
205 *
206 */
netlbl_unlhsh_hash(int ifindex)207 static u32 netlbl_unlhsh_hash(int ifindex)
208 {
209 return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1);
210 }
211
212 /**
213 * netlbl_unlhsh_search_iface - Search for a matching interface entry
214 * @ifindex: the network interface
215 *
216 * Description:
217 * Searches the unlabeled connection hash table and returns a pointer to the
218 * interface entry which matches @ifindex, otherwise NULL is returned. The
219 * caller is responsible for ensuring that the hash table is protected with
220 * either a RCU read lock or the hash table lock.
221 *
222 */
netlbl_unlhsh_search_iface(int ifindex)223 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
224 {
225 u32 bkt;
226 struct list_head *bkt_list;
227 struct netlbl_unlhsh_iface *iter;
228
229 bkt = netlbl_unlhsh_hash(ifindex);
230 bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt];
231 list_for_each_entry_rcu(iter, bkt_list, list)
232 if (iter->valid && iter->ifindex == ifindex)
233 return iter;
234
235 return NULL;
236 }
237
238 /**
239 * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
240 * @iface: the associated interface entry
241 * @addr: IPv4 address in network byte order
242 * @mask: IPv4 address mask in network byte order
243 * @secid: LSM secid value for entry
244 *
245 * Description:
246 * Add a new address entry into the unlabeled connection hash table using the
247 * interface entry specified by @iface. On success zero is returned, otherwise
248 * a negative value is returned.
249 *
250 */
netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface * iface,const struct in_addr * addr,const struct in_addr * mask,u32 secid)251 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
252 const struct in_addr *addr,
253 const struct in_addr *mask,
254 u32 secid)
255 {
256 int ret_val;
257 struct netlbl_unlhsh_addr4 *entry;
258
259 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
260 if (entry == NULL)
261 return -ENOMEM;
262
263 entry->list.addr = addr->s_addr & mask->s_addr;
264 entry->list.mask = mask->s_addr;
265 entry->list.valid = 1;
266 entry->secid = secid;
267
268 spin_lock(&netlbl_unlhsh_lock);
269 ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
270 spin_unlock(&netlbl_unlhsh_lock);
271
272 if (ret_val != 0)
273 kfree(entry);
274 return ret_val;
275 }
276
277 #if IS_ENABLED(CONFIG_IPV6)
278 /**
279 * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
280 * @iface: the associated interface entry
281 * @addr: IPv6 address in network byte order
282 * @mask: IPv6 address mask in network byte order
283 * @secid: LSM secid value for entry
284 *
285 * Description:
286 * Add a new address entry into the unlabeled connection hash table using the
287 * interface entry specified by @iface. On success zero is returned, otherwise
288 * a negative value is returned.
289 *
290 */
netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface * iface,const struct in6_addr * addr,const struct in6_addr * mask,u32 secid)291 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
292 const struct in6_addr *addr,
293 const struct in6_addr *mask,
294 u32 secid)
295 {
296 int ret_val;
297 struct netlbl_unlhsh_addr6 *entry;
298
299 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
300 if (entry == NULL)
301 return -ENOMEM;
302
303 entry->list.addr = *addr;
304 entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
305 entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
306 entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
307 entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
308 entry->list.mask = *mask;
309 entry->list.valid = 1;
310 entry->secid = secid;
311
312 spin_lock(&netlbl_unlhsh_lock);
313 ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
314 spin_unlock(&netlbl_unlhsh_lock);
315
316 if (ret_val != 0)
317 kfree(entry);
318 return 0;
319 }
320 #endif /* IPv6 */
321
322 /**
323 * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
324 * @ifindex: network interface
325 *
326 * Description:
327 * Add a new, empty, interface entry into the unlabeled connection hash table.
328 * On success a pointer to the new interface entry is returned, on failure NULL
329 * is returned.
330 *
331 */
netlbl_unlhsh_add_iface(int ifindex)332 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
333 {
334 u32 bkt;
335 struct netlbl_unlhsh_iface *iface;
336
337 iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
338 if (iface == NULL)
339 return NULL;
340
341 iface->ifindex = ifindex;
342 INIT_LIST_HEAD(&iface->addr4_list);
343 INIT_LIST_HEAD(&iface->addr6_list);
344 iface->valid = 1;
345
346 spin_lock(&netlbl_unlhsh_lock);
347 if (ifindex > 0) {
348 bkt = netlbl_unlhsh_hash(ifindex);
349 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
350 goto add_iface_failure;
351 list_add_tail_rcu(&iface->list,
352 &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]);
353 } else {
354 INIT_LIST_HEAD(&iface->list);
355 if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL)
356 goto add_iface_failure;
357 rcu_assign_pointer(netlbl_unlhsh_def, iface);
358 }
359 spin_unlock(&netlbl_unlhsh_lock);
360
361 return iface;
362
363 add_iface_failure:
364 spin_unlock(&netlbl_unlhsh_lock);
365 kfree(iface);
366 return NULL;
367 }
368
369 /**
370 * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
371 * @net: network namespace
372 * @dev_name: interface name
373 * @addr: IP address in network byte order
374 * @mask: address mask in network byte order
375 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
376 * @secid: LSM secid value for the entry
377 * @audit_info: NetLabel audit information
378 *
379 * Description:
380 * Adds a new entry to the unlabeled connection hash table. Returns zero on
381 * success, negative values on failure.
382 *
383 */
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)384 int netlbl_unlhsh_add(struct net *net,
385 const char *dev_name,
386 const void *addr,
387 const void *mask,
388 u32 addr_len,
389 u32 secid,
390 struct netlbl_audit *audit_info)
391 {
392 int ret_val;
393 int ifindex;
394 struct net_device *dev;
395 struct netlbl_unlhsh_iface *iface;
396 struct audit_buffer *audit_buf = NULL;
397 char *secctx = NULL;
398 u32 secctx_len;
399
400 if (addr_len != sizeof(struct in_addr) &&
401 addr_len != sizeof(struct in6_addr))
402 return -EINVAL;
403
404 rcu_read_lock();
405 if (dev_name != NULL) {
406 dev = dev_get_by_name_rcu(net, dev_name);
407 if (dev == NULL) {
408 ret_val = -ENODEV;
409 goto unlhsh_add_return;
410 }
411 ifindex = dev->ifindex;
412 iface = netlbl_unlhsh_search_iface(ifindex);
413 } else {
414 ifindex = 0;
415 iface = rcu_dereference(netlbl_unlhsh_def);
416 }
417 if (iface == NULL) {
418 iface = netlbl_unlhsh_add_iface(ifindex);
419 if (iface == NULL) {
420 ret_val = -ENOMEM;
421 goto unlhsh_add_return;
422 }
423 }
424 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
425 audit_info);
426 switch (addr_len) {
427 case sizeof(struct in_addr): {
428 const struct in_addr *addr4 = addr;
429 const struct in_addr *mask4 = mask;
430
431 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
432 if (audit_buf != NULL)
433 netlbl_af4list_audit_addr(audit_buf, 1,
434 dev_name,
435 addr4->s_addr,
436 mask4->s_addr);
437 break;
438 }
439 #if IS_ENABLED(CONFIG_IPV6)
440 case sizeof(struct in6_addr): {
441 const struct in6_addr *addr6 = addr;
442 const struct in6_addr *mask6 = mask;
443
444 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
445 if (audit_buf != NULL)
446 netlbl_af6list_audit_addr(audit_buf, 1,
447 dev_name,
448 addr6, mask6);
449 break;
450 }
451 #endif /* IPv6 */
452 default:
453 ret_val = -EINVAL;
454 }
455 if (ret_val == 0)
456 atomic_inc(&netlabel_mgmt_protocount);
457
458 unlhsh_add_return:
459 rcu_read_unlock();
460 if (audit_buf != NULL) {
461 if (security_secid_to_secctx(secid,
462 &secctx,
463 &secctx_len) == 0) {
464 audit_log_format(audit_buf, " sec_obj=%s", secctx);
465 security_release_secctx(secctx, secctx_len);
466 }
467 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
468 audit_log_end(audit_buf);
469 }
470 return ret_val;
471 }
472
473 /**
474 * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
475 * @net: network namespace
476 * @iface: interface entry
477 * @addr: IP address
478 * @mask: IP address mask
479 * @audit_info: NetLabel audit information
480 *
481 * Description:
482 * Remove an IP address entry from the unlabeled connection hash table.
483 * Returns zero on success, negative values on failure.
484 *
485 */
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)486 static int netlbl_unlhsh_remove_addr4(struct net *net,
487 struct netlbl_unlhsh_iface *iface,
488 const struct in_addr *addr,
489 const struct in_addr *mask,
490 struct netlbl_audit *audit_info)
491 {
492 struct netlbl_af4list *list_entry;
493 struct netlbl_unlhsh_addr4 *entry;
494 struct audit_buffer *audit_buf;
495 struct net_device *dev;
496 char *secctx;
497 u32 secctx_len;
498
499 spin_lock(&netlbl_unlhsh_lock);
500 list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
501 &iface->addr4_list);
502 spin_unlock(&netlbl_unlhsh_lock);
503 if (list_entry != NULL)
504 entry = netlbl_unlhsh_addr4_entry(list_entry);
505 else
506 entry = NULL;
507
508 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
509 audit_info);
510 if (audit_buf != NULL) {
511 dev = dev_get_by_index(net, iface->ifindex);
512 netlbl_af4list_audit_addr(audit_buf, 1,
513 (dev != NULL ? dev->name : NULL),
514 addr->s_addr, mask->s_addr);
515 if (dev != NULL)
516 dev_put(dev);
517 if (entry != NULL &&
518 security_secid_to_secctx(entry->secid,
519 &secctx, &secctx_len) == 0) {
520 audit_log_format(audit_buf, " sec_obj=%s", secctx);
521 security_release_secctx(secctx, secctx_len);
522 }
523 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
524 audit_log_end(audit_buf);
525 }
526
527 if (entry == NULL)
528 return -ENOENT;
529
530 kfree_rcu(entry, rcu);
531 return 0;
532 }
533
534 #if IS_ENABLED(CONFIG_IPV6)
535 /**
536 * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
537 * @net: network namespace
538 * @iface: interface entry
539 * @addr: IP address
540 * @mask: IP address mask
541 * @audit_info: NetLabel audit information
542 *
543 * Description:
544 * Remove an IP address entry from the unlabeled connection hash table.
545 * Returns zero on success, negative values on failure.
546 *
547 */
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)548 static int netlbl_unlhsh_remove_addr6(struct net *net,
549 struct netlbl_unlhsh_iface *iface,
550 const struct in6_addr *addr,
551 const struct in6_addr *mask,
552 struct netlbl_audit *audit_info)
553 {
554 struct netlbl_af6list *list_entry;
555 struct netlbl_unlhsh_addr6 *entry;
556 struct audit_buffer *audit_buf;
557 struct net_device *dev;
558 char *secctx;
559 u32 secctx_len;
560
561 spin_lock(&netlbl_unlhsh_lock);
562 list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
563 spin_unlock(&netlbl_unlhsh_lock);
564 if (list_entry != NULL)
565 entry = netlbl_unlhsh_addr6_entry(list_entry);
566 else
567 entry = NULL;
568
569 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
570 audit_info);
571 if (audit_buf != NULL) {
572 dev = dev_get_by_index(net, iface->ifindex);
573 netlbl_af6list_audit_addr(audit_buf, 1,
574 (dev != NULL ? dev->name : NULL),
575 addr, mask);
576 if (dev != NULL)
577 dev_put(dev);
578 if (entry != NULL &&
579 security_secid_to_secctx(entry->secid,
580 &secctx, &secctx_len) == 0) {
581 audit_log_format(audit_buf, " sec_obj=%s", secctx);
582 security_release_secctx(secctx, secctx_len);
583 }
584 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
585 audit_log_end(audit_buf);
586 }
587
588 if (entry == NULL)
589 return -ENOENT;
590
591 kfree_rcu(entry, rcu);
592 return 0;
593 }
594 #endif /* IPv6 */
595
596 /**
597 * netlbl_unlhsh_condremove_iface - Remove an interface entry
598 * @iface: the interface entry
599 *
600 * Description:
601 * Remove an interface entry from the unlabeled connection hash table if it is
602 * empty. An interface entry is considered to be empty if there are no
603 * address entries assigned to it.
604 *
605 */
netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface * iface)606 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
607 {
608 struct netlbl_af4list *iter4;
609 #if IS_ENABLED(CONFIG_IPV6)
610 struct netlbl_af6list *iter6;
611 #endif /* IPv6 */
612
613 spin_lock(&netlbl_unlhsh_lock);
614 netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
615 goto unlhsh_condremove_failure;
616 #if IS_ENABLED(CONFIG_IPV6)
617 netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
618 goto unlhsh_condremove_failure;
619 #endif /* IPv6 */
620 iface->valid = 0;
621 if (iface->ifindex > 0)
622 list_del_rcu(&iface->list);
623 else
624 RCU_INIT_POINTER(netlbl_unlhsh_def, NULL);
625 spin_unlock(&netlbl_unlhsh_lock);
626
627 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
628 return;
629
630 unlhsh_condremove_failure:
631 spin_unlock(&netlbl_unlhsh_lock);
632 }
633
634 /**
635 * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
636 * @net: network namespace
637 * @dev_name: interface name
638 * @addr: IP address in network byte order
639 * @mask: address mask in network byte order
640 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
641 * @audit_info: NetLabel audit information
642 *
643 * Description:
644 * Removes and existing entry from the unlabeled connection hash table.
645 * Returns zero on success, negative values on failure.
646 *
647 */
netlbl_unlhsh_remove(struct net * net,const char * dev_name,const void * addr,const void * mask,u32 addr_len,struct netlbl_audit * audit_info)648 int netlbl_unlhsh_remove(struct net *net,
649 const char *dev_name,
650 const void *addr,
651 const void *mask,
652 u32 addr_len,
653 struct netlbl_audit *audit_info)
654 {
655 int ret_val;
656 struct net_device *dev;
657 struct netlbl_unlhsh_iface *iface;
658
659 if (addr_len != sizeof(struct in_addr) &&
660 addr_len != sizeof(struct in6_addr))
661 return -EINVAL;
662
663 rcu_read_lock();
664 if (dev_name != NULL) {
665 dev = dev_get_by_name_rcu(net, dev_name);
666 if (dev == NULL) {
667 ret_val = -ENODEV;
668 goto unlhsh_remove_return;
669 }
670 iface = netlbl_unlhsh_search_iface(dev->ifindex);
671 } else
672 iface = rcu_dereference(netlbl_unlhsh_def);
673 if (iface == NULL) {
674 ret_val = -ENOENT;
675 goto unlhsh_remove_return;
676 }
677 switch (addr_len) {
678 case sizeof(struct in_addr):
679 ret_val = netlbl_unlhsh_remove_addr4(net,
680 iface, addr, mask,
681 audit_info);
682 break;
683 #if IS_ENABLED(CONFIG_IPV6)
684 case sizeof(struct in6_addr):
685 ret_val = netlbl_unlhsh_remove_addr6(net,
686 iface, addr, mask,
687 audit_info);
688 break;
689 #endif /* IPv6 */
690 default:
691 ret_val = -EINVAL;
692 }
693 if (ret_val == 0) {
694 netlbl_unlhsh_condremove_iface(iface);
695 atomic_dec(&netlabel_mgmt_protocount);
696 }
697
698 unlhsh_remove_return:
699 rcu_read_unlock();
700 return ret_val;
701 }
702
703 /*
704 * General Helper Functions
705 */
706
707 /**
708 * netlbl_unlhsh_netdev_handler - Network device notification handler
709 * @this: notifier block
710 * @event: the event
711 * @ptr: the network device (cast to void)
712 *
713 * Description:
714 * Handle network device events, although at present all we care about is a
715 * network device going away. In the case of a device going away we clear any
716 * related entries from the unlabeled connection hash table.
717 *
718 */
netlbl_unlhsh_netdev_handler(struct notifier_block * this,unsigned long event,void * ptr)719 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
720 unsigned long event,
721 void *ptr)
722 {
723 struct net_device *dev = ptr;
724 struct netlbl_unlhsh_iface *iface = NULL;
725
726 if (!net_eq(dev_net(dev), &init_net))
727 return NOTIFY_DONE;
728
729 /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
730 if (event == NETDEV_DOWN) {
731 spin_lock(&netlbl_unlhsh_lock);
732 iface = netlbl_unlhsh_search_iface(dev->ifindex);
733 if (iface != NULL && iface->valid) {
734 iface->valid = 0;
735 list_del_rcu(&iface->list);
736 } else
737 iface = NULL;
738 spin_unlock(&netlbl_unlhsh_lock);
739 }
740
741 if (iface != NULL)
742 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
743
744 return NOTIFY_DONE;
745 }
746
747 /**
748 * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
749 * @value: desired value
750 * @audit_info: NetLabel audit information
751 *
752 * Description:
753 * Set the value of the unlabeled accept flag to @value.
754 *
755 */
netlbl_unlabel_acceptflg_set(u8 value,struct netlbl_audit * audit_info)756 static void netlbl_unlabel_acceptflg_set(u8 value,
757 struct netlbl_audit *audit_info)
758 {
759 struct audit_buffer *audit_buf;
760 u8 old_val;
761
762 old_val = netlabel_unlabel_acceptflg;
763 netlabel_unlabel_acceptflg = value;
764 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
765 audit_info);
766 if (audit_buf != NULL) {
767 audit_log_format(audit_buf,
768 " unlbl_accept=%u old=%u", value, old_val);
769 audit_log_end(audit_buf);
770 }
771 }
772
773 /**
774 * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
775 * @info: the Generic NETLINK info block
776 * @addr: the IP address
777 * @mask: the IP address mask
778 * @len: the address length
779 *
780 * Description:
781 * Examine the Generic NETLINK message and extract the IP address information.
782 * Returns zero on success, negative values on failure.
783 *
784 */
netlbl_unlabel_addrinfo_get(struct genl_info * info,void ** addr,void ** mask,u32 * len)785 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
786 void **addr,
787 void **mask,
788 u32 *len)
789 {
790 u32 addr_len;
791
792 if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
793 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
794 if (addr_len != sizeof(struct in_addr) &&
795 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
796 return -EINVAL;
797 *len = addr_len;
798 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
799 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
800 return 0;
801 } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
802 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
803 if (addr_len != sizeof(struct in6_addr) &&
804 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
805 return -EINVAL;
806 *len = addr_len;
807 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
808 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
809 return 0;
810 }
811
812 return -EINVAL;
813 }
814
815 /*
816 * NetLabel Command Handlers
817 */
818
819 /**
820 * netlbl_unlabel_accept - Handle an ACCEPT message
821 * @skb: the NETLINK buffer
822 * @info: the Generic NETLINK info block
823 *
824 * Description:
825 * Process a user generated ACCEPT message and set the accept flag accordingly.
826 * Returns zero on success, negative values on failure.
827 *
828 */
netlbl_unlabel_accept(struct sk_buff * skb,struct genl_info * info)829 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
830 {
831 u8 value;
832 struct netlbl_audit audit_info;
833
834 if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
835 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
836 if (value == 1 || value == 0) {
837 netlbl_netlink_auditinfo(skb, &audit_info);
838 netlbl_unlabel_acceptflg_set(value, &audit_info);
839 return 0;
840 }
841 }
842
843 return -EINVAL;
844 }
845
846 /**
847 * netlbl_unlabel_list - Handle a LIST message
848 * @skb: the NETLINK buffer
849 * @info: the Generic NETLINK info block
850 *
851 * Description:
852 * Process a user generated LIST message and respond with the current status.
853 * Returns zero on success, negative values on failure.
854 *
855 */
netlbl_unlabel_list(struct sk_buff * skb,struct genl_info * info)856 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
857 {
858 int ret_val = -EINVAL;
859 struct sk_buff *ans_skb;
860 void *data;
861
862 ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
863 if (ans_skb == NULL)
864 goto list_failure;
865 data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
866 0, NLBL_UNLABEL_C_LIST);
867 if (data == NULL) {
868 ret_val = -ENOMEM;
869 goto list_failure;
870 }
871
872 ret_val = nla_put_u8(ans_skb,
873 NLBL_UNLABEL_A_ACPTFLG,
874 netlabel_unlabel_acceptflg);
875 if (ret_val != 0)
876 goto list_failure;
877
878 genlmsg_end(ans_skb, data);
879 return genlmsg_reply(ans_skb, info);
880
881 list_failure:
882 kfree_skb(ans_skb);
883 return ret_val;
884 }
885
886 /**
887 * netlbl_unlabel_staticadd - Handle a STATICADD message
888 * @skb: the NETLINK buffer
889 * @info: the Generic NETLINK info block
890 *
891 * Description:
892 * Process a user generated STATICADD message and add a new unlabeled
893 * connection entry to the hash table. Returns zero on success, negative
894 * values on failure.
895 *
896 */
netlbl_unlabel_staticadd(struct sk_buff * skb,struct genl_info * info)897 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
898 struct genl_info *info)
899 {
900 int ret_val;
901 char *dev_name;
902 void *addr;
903 void *mask;
904 u32 addr_len;
905 u32 secid;
906 struct netlbl_audit audit_info;
907
908 /* Don't allow users to add both IPv4 and IPv6 addresses for a
909 * single entry. However, allow users to create two entries, one each
910 * for IPv4 and IPv4, with the same LSM security context which should
911 * achieve the same result. */
912 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
913 !info->attrs[NLBL_UNLABEL_A_IFACE] ||
914 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
915 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
916 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
917 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
918 return -EINVAL;
919
920 netlbl_netlink_auditinfo(skb, &audit_info);
921
922 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
923 if (ret_val != 0)
924 return ret_val;
925 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
926 ret_val = security_secctx_to_secid(
927 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
928 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
929 &secid);
930 if (ret_val != 0)
931 return ret_val;
932
933 return netlbl_unlhsh_add(&init_net,
934 dev_name, addr, mask, addr_len, secid,
935 &audit_info);
936 }
937
938 /**
939 * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
940 * @skb: the NETLINK buffer
941 * @info: the Generic NETLINK info block
942 *
943 * Description:
944 * Process a user generated STATICADDDEF message and add a new default
945 * unlabeled connection entry. Returns zero on success, negative values on
946 * failure.
947 *
948 */
netlbl_unlabel_staticadddef(struct sk_buff * skb,struct genl_info * info)949 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
950 struct genl_info *info)
951 {
952 int ret_val;
953 void *addr;
954 void *mask;
955 u32 addr_len;
956 u32 secid;
957 struct netlbl_audit audit_info;
958
959 /* Don't allow users to add both IPv4 and IPv6 addresses for a
960 * single entry. However, allow users to create two entries, one each
961 * for IPv4 and IPv6, with the same LSM security context which should
962 * achieve the same result. */
963 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
964 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
965 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
966 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
967 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
968 return -EINVAL;
969
970 netlbl_netlink_auditinfo(skb, &audit_info);
971
972 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
973 if (ret_val != 0)
974 return ret_val;
975 ret_val = security_secctx_to_secid(
976 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
977 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
978 &secid);
979 if (ret_val != 0)
980 return ret_val;
981
982 return netlbl_unlhsh_add(&init_net,
983 NULL, addr, mask, addr_len, secid,
984 &audit_info);
985 }
986
987 /**
988 * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
989 * @skb: the NETLINK buffer
990 * @info: the Generic NETLINK info block
991 *
992 * Description:
993 * Process a user generated STATICREMOVE message and remove the specified
994 * unlabeled connection entry. Returns zero on success, negative values on
995 * failure.
996 *
997 */
netlbl_unlabel_staticremove(struct sk_buff * skb,struct genl_info * info)998 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
999 struct genl_info *info)
1000 {
1001 int ret_val;
1002 char *dev_name;
1003 void *addr;
1004 void *mask;
1005 u32 addr_len;
1006 struct netlbl_audit audit_info;
1007
1008 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1009 * IPv4 and IPv6 in the same entry. */
1010 if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1011 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1012 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1013 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1014 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1015 return -EINVAL;
1016
1017 netlbl_netlink_auditinfo(skb, &audit_info);
1018
1019 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1020 if (ret_val != 0)
1021 return ret_val;
1022 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1023
1024 return netlbl_unlhsh_remove(&init_net,
1025 dev_name, addr, mask, addr_len,
1026 &audit_info);
1027 }
1028
1029 /**
1030 * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1031 * @skb: the NETLINK buffer
1032 * @info: the Generic NETLINK info block
1033 *
1034 * Description:
1035 * Process a user generated STATICREMOVEDEF message and remove the default
1036 * unlabeled connection entry. Returns zero on success, negative values on
1037 * failure.
1038 *
1039 */
netlbl_unlabel_staticremovedef(struct sk_buff * skb,struct genl_info * info)1040 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1041 struct genl_info *info)
1042 {
1043 int ret_val;
1044 void *addr;
1045 void *mask;
1046 u32 addr_len;
1047 struct netlbl_audit audit_info;
1048
1049 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1050 * IPv4 and IPv6 in the same entry. */
1051 if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1052 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1053 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1054 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1055 return -EINVAL;
1056
1057 netlbl_netlink_auditinfo(skb, &audit_info);
1058
1059 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1060 if (ret_val != 0)
1061 return ret_val;
1062
1063 return netlbl_unlhsh_remove(&init_net,
1064 NULL, addr, mask, addr_len,
1065 &audit_info);
1066 }
1067
1068
1069 /**
1070 * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1071 * @cmd: command/message
1072 * @iface: the interface entry
1073 * @addr4: the IPv4 address entry
1074 * @addr6: the IPv6 address entry
1075 * @arg: the netlbl_unlhsh_walk_arg structure
1076 *
1077 * Description:
1078 * This function is designed to be used to generate a response for a
1079 * STATICLIST or STATICLISTDEF message. When called either @addr4 or @addr6
1080 * can be specified, not both, the other unspecified entry should be set to
1081 * NULL by the caller. Returns the size of the message on success, negative
1082 * values on failure.
1083 *
1084 */
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)1085 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1086 const struct netlbl_unlhsh_iface *iface,
1087 const struct netlbl_unlhsh_addr4 *addr4,
1088 const struct netlbl_unlhsh_addr6 *addr6,
1089 void *arg)
1090 {
1091 int ret_val = -ENOMEM;
1092 struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1093 struct net_device *dev;
1094 void *data;
1095 u32 secid;
1096 char *secctx;
1097 u32 secctx_len;
1098
1099 data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
1100 cb_arg->seq, &netlbl_unlabel_gnl_family,
1101 NLM_F_MULTI, cmd);
1102 if (data == NULL)
1103 goto list_cb_failure;
1104
1105 if (iface->ifindex > 0) {
1106 dev = dev_get_by_index(&init_net, iface->ifindex);
1107 if (!dev) {
1108 ret_val = -ENODEV;
1109 goto list_cb_failure;
1110 }
1111 ret_val = nla_put_string(cb_arg->skb,
1112 NLBL_UNLABEL_A_IFACE, dev->name);
1113 dev_put(dev);
1114 if (ret_val != 0)
1115 goto list_cb_failure;
1116 }
1117
1118 if (addr4) {
1119 struct in_addr addr_struct;
1120
1121 addr_struct.s_addr = addr4->list.addr;
1122 ret_val = nla_put(cb_arg->skb,
1123 NLBL_UNLABEL_A_IPV4ADDR,
1124 sizeof(struct in_addr),
1125 &addr_struct);
1126 if (ret_val != 0)
1127 goto list_cb_failure;
1128
1129 addr_struct.s_addr = addr4->list.mask;
1130 ret_val = nla_put(cb_arg->skb,
1131 NLBL_UNLABEL_A_IPV4MASK,
1132 sizeof(struct in_addr),
1133 &addr_struct);
1134 if (ret_val != 0)
1135 goto list_cb_failure;
1136
1137 secid = addr4->secid;
1138 } else {
1139 ret_val = nla_put(cb_arg->skb,
1140 NLBL_UNLABEL_A_IPV6ADDR,
1141 sizeof(struct in6_addr),
1142 &addr6->list.addr);
1143 if (ret_val != 0)
1144 goto list_cb_failure;
1145
1146 ret_val = nla_put(cb_arg->skb,
1147 NLBL_UNLABEL_A_IPV6MASK,
1148 sizeof(struct in6_addr),
1149 &addr6->list.mask);
1150 if (ret_val != 0)
1151 goto list_cb_failure;
1152
1153 secid = addr6->secid;
1154 }
1155
1156 ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1157 if (ret_val != 0)
1158 goto list_cb_failure;
1159 ret_val = nla_put(cb_arg->skb,
1160 NLBL_UNLABEL_A_SECCTX,
1161 secctx_len,
1162 secctx);
1163 security_release_secctx(secctx, secctx_len);
1164 if (ret_val != 0)
1165 goto list_cb_failure;
1166
1167 cb_arg->seq++;
1168 return genlmsg_end(cb_arg->skb, data);
1169
1170 list_cb_failure:
1171 genlmsg_cancel(cb_arg->skb, data);
1172 return ret_val;
1173 }
1174
1175 /**
1176 * netlbl_unlabel_staticlist - Handle a STATICLIST message
1177 * @skb: the NETLINK buffer
1178 * @cb: the NETLINK callback
1179 *
1180 * Description:
1181 * Process a user generated STATICLIST message and dump the unlabeled
1182 * connection hash table in a form suitable for use in a kernel generated
1183 * STATICLIST message. Returns the length of @skb.
1184 *
1185 */
netlbl_unlabel_staticlist(struct sk_buff * skb,struct netlink_callback * cb)1186 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1187 struct netlink_callback *cb)
1188 {
1189 struct netlbl_unlhsh_walk_arg cb_arg;
1190 u32 skip_bkt = cb->args[0];
1191 u32 skip_chain = cb->args[1];
1192 u32 iter_bkt;
1193 u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1194 struct netlbl_unlhsh_iface *iface;
1195 struct list_head *iter_list;
1196 struct netlbl_af4list *addr4;
1197 #if IS_ENABLED(CONFIG_IPV6)
1198 struct netlbl_af6list *addr6;
1199 #endif
1200
1201 cb_arg.nl_cb = cb;
1202 cb_arg.skb = skb;
1203 cb_arg.seq = cb->nlh->nlmsg_seq;
1204
1205 rcu_read_lock();
1206 for (iter_bkt = skip_bkt;
1207 iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1208 iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1209 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1210 list_for_each_entry_rcu(iface, iter_list, list) {
1211 if (!iface->valid ||
1212 iter_chain++ < skip_chain)
1213 continue;
1214 netlbl_af4list_foreach_rcu(addr4,
1215 &iface->addr4_list) {
1216 if (iter_addr4++ < cb->args[2])
1217 continue;
1218 if (netlbl_unlabel_staticlist_gen(
1219 NLBL_UNLABEL_C_STATICLIST,
1220 iface,
1221 netlbl_unlhsh_addr4_entry(addr4),
1222 NULL,
1223 &cb_arg) < 0) {
1224 iter_addr4--;
1225 iter_chain--;
1226 goto unlabel_staticlist_return;
1227 }
1228 }
1229 #if IS_ENABLED(CONFIG_IPV6)
1230 netlbl_af6list_foreach_rcu(addr6,
1231 &iface->addr6_list) {
1232 if (iter_addr6++ < cb->args[3])
1233 continue;
1234 if (netlbl_unlabel_staticlist_gen(
1235 NLBL_UNLABEL_C_STATICLIST,
1236 iface,
1237 NULL,
1238 netlbl_unlhsh_addr6_entry(addr6),
1239 &cb_arg) < 0) {
1240 iter_addr6--;
1241 iter_chain--;
1242 goto unlabel_staticlist_return;
1243 }
1244 }
1245 #endif /* IPv6 */
1246 }
1247 }
1248
1249 unlabel_staticlist_return:
1250 rcu_read_unlock();
1251 cb->args[0] = iter_bkt;
1252 cb->args[1] = iter_chain;
1253 cb->args[2] = iter_addr4;
1254 cb->args[3] = iter_addr6;
1255 return skb->len;
1256 }
1257
1258 /**
1259 * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1260 * @skb: the NETLINK buffer
1261 * @cb: the NETLINK callback
1262 *
1263 * Description:
1264 * Process a user generated STATICLISTDEF message and dump the default
1265 * unlabeled connection entry in a form suitable for use in a kernel generated
1266 * STATICLISTDEF message. Returns the length of @skb.
1267 *
1268 */
netlbl_unlabel_staticlistdef(struct sk_buff * skb,struct netlink_callback * cb)1269 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1270 struct netlink_callback *cb)
1271 {
1272 struct netlbl_unlhsh_walk_arg cb_arg;
1273 struct netlbl_unlhsh_iface *iface;
1274 u32 iter_addr4 = 0, iter_addr6 = 0;
1275 struct netlbl_af4list *addr4;
1276 #if IS_ENABLED(CONFIG_IPV6)
1277 struct netlbl_af6list *addr6;
1278 #endif
1279
1280 cb_arg.nl_cb = cb;
1281 cb_arg.skb = skb;
1282 cb_arg.seq = cb->nlh->nlmsg_seq;
1283
1284 rcu_read_lock();
1285 iface = rcu_dereference(netlbl_unlhsh_def);
1286 if (iface == NULL || !iface->valid)
1287 goto unlabel_staticlistdef_return;
1288
1289 netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1290 if (iter_addr4++ < cb->args[0])
1291 continue;
1292 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1293 iface,
1294 netlbl_unlhsh_addr4_entry(addr4),
1295 NULL,
1296 &cb_arg) < 0) {
1297 iter_addr4--;
1298 goto unlabel_staticlistdef_return;
1299 }
1300 }
1301 #if IS_ENABLED(CONFIG_IPV6)
1302 netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1303 if (iter_addr6++ < cb->args[1])
1304 continue;
1305 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1306 iface,
1307 NULL,
1308 netlbl_unlhsh_addr6_entry(addr6),
1309 &cb_arg) < 0) {
1310 iter_addr6--;
1311 goto unlabel_staticlistdef_return;
1312 }
1313 }
1314 #endif /* IPv6 */
1315
1316 unlabel_staticlistdef_return:
1317 rcu_read_unlock();
1318 cb->args[0] = iter_addr4;
1319 cb->args[1] = iter_addr6;
1320 return skb->len;
1321 }
1322
1323 /*
1324 * NetLabel Generic NETLINK Command Definitions
1325 */
1326
1327 static struct genl_ops netlbl_unlabel_genl_ops[] = {
1328 {
1329 .cmd = NLBL_UNLABEL_C_STATICADD,
1330 .flags = GENL_ADMIN_PERM,
1331 .policy = netlbl_unlabel_genl_policy,
1332 .doit = netlbl_unlabel_staticadd,
1333 .dumpit = NULL,
1334 },
1335 {
1336 .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1337 .flags = GENL_ADMIN_PERM,
1338 .policy = netlbl_unlabel_genl_policy,
1339 .doit = netlbl_unlabel_staticremove,
1340 .dumpit = NULL,
1341 },
1342 {
1343 .cmd = NLBL_UNLABEL_C_STATICLIST,
1344 .flags = 0,
1345 .policy = netlbl_unlabel_genl_policy,
1346 .doit = NULL,
1347 .dumpit = netlbl_unlabel_staticlist,
1348 },
1349 {
1350 .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1351 .flags = GENL_ADMIN_PERM,
1352 .policy = netlbl_unlabel_genl_policy,
1353 .doit = netlbl_unlabel_staticadddef,
1354 .dumpit = NULL,
1355 },
1356 {
1357 .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1358 .flags = GENL_ADMIN_PERM,
1359 .policy = netlbl_unlabel_genl_policy,
1360 .doit = netlbl_unlabel_staticremovedef,
1361 .dumpit = NULL,
1362 },
1363 {
1364 .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1365 .flags = 0,
1366 .policy = netlbl_unlabel_genl_policy,
1367 .doit = NULL,
1368 .dumpit = netlbl_unlabel_staticlistdef,
1369 },
1370 {
1371 .cmd = NLBL_UNLABEL_C_ACCEPT,
1372 .flags = GENL_ADMIN_PERM,
1373 .policy = netlbl_unlabel_genl_policy,
1374 .doit = netlbl_unlabel_accept,
1375 .dumpit = NULL,
1376 },
1377 {
1378 .cmd = NLBL_UNLABEL_C_LIST,
1379 .flags = 0,
1380 .policy = netlbl_unlabel_genl_policy,
1381 .doit = netlbl_unlabel_list,
1382 .dumpit = NULL,
1383 },
1384 };
1385
1386 /*
1387 * NetLabel Generic NETLINK Protocol Functions
1388 */
1389
1390 /**
1391 * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1392 *
1393 * Description:
1394 * Register the unlabeled packet NetLabel component with the Generic NETLINK
1395 * mechanism. Returns zero on success, negative values on failure.
1396 *
1397 */
netlbl_unlabel_genl_init(void)1398 int __init netlbl_unlabel_genl_init(void)
1399 {
1400 return genl_register_family_with_ops(&netlbl_unlabel_gnl_family,
1401 netlbl_unlabel_genl_ops, ARRAY_SIZE(netlbl_unlabel_genl_ops));
1402 }
1403
1404 /*
1405 * NetLabel KAPI Hooks
1406 */
1407
1408 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1409 .notifier_call = netlbl_unlhsh_netdev_handler,
1410 };
1411
1412 /**
1413 * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1414 * @size: the number of bits to use for the hash buckets
1415 *
1416 * Description:
1417 * Initializes the unlabeled connection hash table and registers a network
1418 * device notification handler. This function should only be called by the
1419 * NetLabel subsystem itself during initialization. Returns zero on success,
1420 * non-zero values on error.
1421 *
1422 */
netlbl_unlabel_init(u32 size)1423 int __init netlbl_unlabel_init(u32 size)
1424 {
1425 u32 iter;
1426 struct netlbl_unlhsh_tbl *hsh_tbl;
1427
1428 if (size == 0)
1429 return -EINVAL;
1430
1431 hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1432 if (hsh_tbl == NULL)
1433 return -ENOMEM;
1434 hsh_tbl->size = 1 << size;
1435 hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1436 sizeof(struct list_head),
1437 GFP_KERNEL);
1438 if (hsh_tbl->tbl == NULL) {
1439 kfree(hsh_tbl);
1440 return -ENOMEM;
1441 }
1442 for (iter = 0; iter < hsh_tbl->size; iter++)
1443 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1444
1445 spin_lock(&netlbl_unlhsh_lock);
1446 rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1447 spin_unlock(&netlbl_unlhsh_lock);
1448
1449 register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1450
1451 return 0;
1452 }
1453
1454 /**
1455 * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1456 * @skb: the packet
1457 * @family: protocol family
1458 * @secattr: the security attributes
1459 *
1460 * Description:
1461 * Determine the security attributes, if any, for an unlabled packet and return
1462 * them in @secattr. Returns zero on success and negative values on failure.
1463 *
1464 */
netlbl_unlabel_getattr(const struct sk_buff * skb,u16 family,struct netlbl_lsm_secattr * secattr)1465 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1466 u16 family,
1467 struct netlbl_lsm_secattr *secattr)
1468 {
1469 struct netlbl_unlhsh_iface *iface;
1470
1471 rcu_read_lock();
1472 iface = netlbl_unlhsh_search_iface(skb->skb_iif);
1473 if (iface == NULL)
1474 iface = rcu_dereference(netlbl_unlhsh_def);
1475 if (iface == NULL || !iface->valid)
1476 goto unlabel_getattr_nolabel;
1477 switch (family) {
1478 case PF_INET: {
1479 struct iphdr *hdr4;
1480 struct netlbl_af4list *addr4;
1481
1482 hdr4 = ip_hdr(skb);
1483 addr4 = netlbl_af4list_search(hdr4->saddr,
1484 &iface->addr4_list);
1485 if (addr4 == NULL)
1486 goto unlabel_getattr_nolabel;
1487 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1488 break;
1489 }
1490 #if IS_ENABLED(CONFIG_IPV6)
1491 case PF_INET6: {
1492 struct ipv6hdr *hdr6;
1493 struct netlbl_af6list *addr6;
1494
1495 hdr6 = ipv6_hdr(skb);
1496 addr6 = netlbl_af6list_search(&hdr6->saddr,
1497 &iface->addr6_list);
1498 if (addr6 == NULL)
1499 goto unlabel_getattr_nolabel;
1500 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1501 break;
1502 }
1503 #endif /* IPv6 */
1504 default:
1505 goto unlabel_getattr_nolabel;
1506 }
1507 rcu_read_unlock();
1508
1509 secattr->flags |= NETLBL_SECATTR_SECID;
1510 secattr->type = NETLBL_NLTYPE_UNLABELED;
1511 return 0;
1512
1513 unlabel_getattr_nolabel:
1514 rcu_read_unlock();
1515 if (netlabel_unlabel_acceptflg == 0)
1516 return -ENOMSG;
1517 secattr->type = NETLBL_NLTYPE_UNLABELED;
1518 return 0;
1519 }
1520
1521 /**
1522 * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1523 *
1524 * Description:
1525 * Set the default NetLabel configuration to allow incoming unlabeled packets
1526 * and to send unlabeled network traffic by default.
1527 *
1528 */
netlbl_unlabel_defconf(void)1529 int __init netlbl_unlabel_defconf(void)
1530 {
1531 int ret_val;
1532 struct netlbl_dom_map *entry;
1533 struct netlbl_audit audit_info;
1534
1535 /* Only the kernel is allowed to call this function and the only time
1536 * it is called is at bootup before the audit subsystem is reporting
1537 * messages so don't worry to much about these values. */
1538 security_task_getsecid(current, &audit_info.secid);
1539 audit_info.loginuid = 0;
1540 audit_info.sessionid = 0;
1541
1542 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1543 if (entry == NULL)
1544 return -ENOMEM;
1545 entry->type = NETLBL_NLTYPE_UNLABELED;
1546 ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1547 if (ret_val != 0)
1548 return ret_val;
1549
1550 netlbl_unlabel_acceptflg_set(1, &audit_info);
1551
1552 return 0;
1553 }
1554