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.moore@hp.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 <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 <asm/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 static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL;
118 static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL;
119 
120 /* Accept unlabeled packets flag */
121 static u8 netlabel_unlabel_acceptflg = 0;
122 
123 /* NetLabel Generic NETLINK unlabeled family */
124 static struct genl_family netlbl_unlabel_gnl_family = {
125 	.id = GENL_ID_GENERATE,
126 	.hdrsize = 0,
127 	.name = NETLBL_NLTYPE_UNLABELED_NAME,
128 	.version = NETLBL_PROTO_VERSION,
129 	.maxattr = NLBL_UNLABEL_A_MAX,
130 };
131 
132 /* NetLabel Netlink attribute policy */
133 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
134 	[NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
135 	[NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
136 				      .len = sizeof(struct in6_addr) },
137 	[NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
138 				      .len = sizeof(struct in6_addr) },
139 	[NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
140 				      .len = sizeof(struct in_addr) },
141 	[NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
142 				      .len = sizeof(struct in_addr) },
143 	[NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
144 				   .len = IFNAMSIZ - 1 },
145 	[NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
146 };
147 
148 /*
149  * Unlabeled Connection Hash Table Functions
150  */
151 
152 /**
153  * netlbl_unlhsh_free_addr4 - Frees an IPv4 address entry from the hash table
154  * @entry: the entry's RCU field
155  *
156  * Description:
157  * This function is designed to be used as a callback to the call_rcu()
158  * function so that memory allocated to a hash table address entry can be
159  * released safely.
160  *
161  */
162 static void netlbl_unlhsh_free_addr4(struct rcu_head *entry)
163 {
164 	struct netlbl_unlhsh_addr4 *ptr;
165 
166 	ptr = container_of(entry, struct netlbl_unlhsh_addr4, rcu);
167 	kfree(ptr);
168 }
169 
170 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
171 /**
172  * netlbl_unlhsh_free_addr6 - Frees an IPv6 address entry from the hash table
173  * @entry: the entry's RCU field
174  *
175  * Description:
176  * This function is designed to be used as a callback to the call_rcu()
177  * function so that memory allocated to a hash table address entry can be
178  * released safely.
179  *
180  */
181 static void netlbl_unlhsh_free_addr6(struct rcu_head *entry)
182 {
183 	struct netlbl_unlhsh_addr6 *ptr;
184 
185 	ptr = container_of(entry, struct netlbl_unlhsh_addr6, rcu);
186 	kfree(ptr);
187 }
188 #endif /* IPv6 */
189 
190 /**
191  * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
192  * @entry: the entry's RCU field
193  *
194  * Description:
195  * This function is designed to be used as a callback to the call_rcu()
196  * function so that memory allocated to a hash table interface entry can be
197  * released safely.  It is important to note that this function does not free
198  * the IPv4 and IPv6 address lists contained as part of an interface entry.  It
199  * is up to the rest of the code to make sure an interface entry is only freed
200  * once it's address lists are empty.
201  *
202  */
203 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
204 {
205 	struct netlbl_unlhsh_iface *iface;
206 	struct netlbl_af4list *iter4;
207 	struct netlbl_af4list *tmp4;
208 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
209 	struct netlbl_af6list *iter6;
210 	struct netlbl_af6list *tmp6;
211 #endif /* IPv6 */
212 
213 	iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
214 
215 	/* no need for locks here since we are the only one with access to this
216 	 * structure */
217 
218 	netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
219 		netlbl_af4list_remove_entry(iter4);
220 		kfree(netlbl_unlhsh_addr4_entry(iter4));
221 	}
222 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
223 	netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
224 		netlbl_af6list_remove_entry(iter6);
225 		kfree(netlbl_unlhsh_addr6_entry(iter6));
226 	}
227 #endif /* IPv6 */
228 	kfree(iface);
229 }
230 
231 /**
232  * netlbl_unlhsh_hash - Hashing function for the hash table
233  * @ifindex: the network interface/device to hash
234  *
235  * Description:
236  * This is the hashing function for the unlabeled hash table, it returns the
237  * bucket number for the given device/interface.  The caller is responsible for
238  * calling the rcu_read_[un]lock() functions.
239  *
240  */
241 static u32 netlbl_unlhsh_hash(int ifindex)
242 {
243 	/* this is taken _almost_ directly from
244 	 * security/selinux/netif.c:sel_netif_hasfn() as they do pretty much
245 	 * the same thing */
246 	return ifindex & (rcu_dereference(netlbl_unlhsh)->size - 1);
247 }
248 
249 /**
250  * netlbl_unlhsh_search_iface - Search for a matching interface entry
251  * @ifindex: the network interface
252  *
253  * Description:
254  * Searches the unlabeled connection hash table and returns a pointer to the
255  * interface entry which matches @ifindex, otherwise NULL is returned.  The
256  * caller is responsible for calling the rcu_read_[un]lock() functions.
257  *
258  */
259 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
260 {
261 	u32 bkt;
262 	struct list_head *bkt_list;
263 	struct netlbl_unlhsh_iface *iter;
264 
265 	bkt = netlbl_unlhsh_hash(ifindex);
266 	bkt_list = &rcu_dereference(netlbl_unlhsh)->tbl[bkt];
267 	list_for_each_entry_rcu(iter, bkt_list, list)
268 		if (iter->valid && iter->ifindex == ifindex)
269 			return iter;
270 
271 	return NULL;
272 }
273 
274 /**
275  * netlbl_unlhsh_search_iface_def - Search for a matching interface entry
276  * @ifindex: the network interface
277  *
278  * Description:
279  * Searches the unlabeled connection hash table and returns a pointer to the
280  * interface entry which matches @ifindex.  If an exact match can not be found
281  * and there is a valid default entry, the default entry is returned, otherwise
282  * NULL is returned.  The caller is responsible for calling the
283  * rcu_read_[un]lock() functions.
284  *
285  */
286 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface_def(int ifindex)
287 {
288 	struct netlbl_unlhsh_iface *entry;
289 
290 	entry = netlbl_unlhsh_search_iface(ifindex);
291 	if (entry != NULL)
292 		return entry;
293 
294 	entry = rcu_dereference(netlbl_unlhsh_def);
295 	if (entry != NULL && entry->valid)
296 		return entry;
297 
298 	return NULL;
299 }
300 
301 /**
302  * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
303  * @iface: the associated interface entry
304  * @addr: IPv4 address in network byte order
305  * @mask: IPv4 address mask in network byte order
306  * @secid: LSM secid value for entry
307  *
308  * Description:
309  * Add a new address entry into the unlabeled connection hash table using the
310  * interface entry specified by @iface.  On success zero is returned, otherwise
311  * a negative value is returned.  The caller is responsible for calling the
312  * rcu_read_[un]lock() functions.
313  *
314  */
315 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
316 				   const struct in_addr *addr,
317 				   const struct in_addr *mask,
318 				   u32 secid)
319 {
320 	int ret_val;
321 	struct netlbl_unlhsh_addr4 *entry;
322 
323 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
324 	if (entry == NULL)
325 		return -ENOMEM;
326 
327 	entry->list.addr = addr->s_addr & mask->s_addr;
328 	entry->list.mask = mask->s_addr;
329 	entry->list.valid = 1;
330 	INIT_RCU_HEAD(&entry->rcu);
331 	entry->secid = secid;
332 
333 	spin_lock(&netlbl_unlhsh_lock);
334 	ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
335 	spin_unlock(&netlbl_unlhsh_lock);
336 
337 	if (ret_val != 0)
338 		kfree(entry);
339 	return ret_val;
340 }
341 
342 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
343 /**
344  * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
345  * @iface: the associated interface entry
346  * @addr: IPv6 address in network byte order
347  * @mask: IPv6 address mask in network byte order
348  * @secid: LSM secid value for entry
349  *
350  * Description:
351  * Add a new address entry into the unlabeled connection hash table using the
352  * interface entry specified by @iface.  On success zero is returned, otherwise
353  * a negative value is returned.  The caller is responsible for calling the
354  * rcu_read_[un]lock() functions.
355  *
356  */
357 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
358 				   const struct in6_addr *addr,
359 				   const struct in6_addr *mask,
360 				   u32 secid)
361 {
362 	int ret_val;
363 	struct netlbl_unlhsh_addr6 *entry;
364 
365 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
366 	if (entry == NULL)
367 		return -ENOMEM;
368 
369 	ipv6_addr_copy(&entry->list.addr, addr);
370 	entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
371 	entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
372 	entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
373 	entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
374 	ipv6_addr_copy(&entry->list.mask, mask);
375 	entry->list.valid = 1;
376 	INIT_RCU_HEAD(&entry->rcu);
377 	entry->secid = secid;
378 
379 	spin_lock(&netlbl_unlhsh_lock);
380 	ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
381 	spin_unlock(&netlbl_unlhsh_lock);
382 
383 	if (ret_val != 0)
384 		kfree(entry);
385 	return 0;
386 }
387 #endif /* IPv6 */
388 
389 /**
390  * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
391  * @ifindex: network interface
392  *
393  * Description:
394  * Add a new, empty, interface entry into the unlabeled connection hash table.
395  * On success a pointer to the new interface entry is returned, on failure NULL
396  * is returned.  The caller is responsible for calling the rcu_read_[un]lock()
397  * functions.
398  *
399  */
400 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
401 {
402 	u32 bkt;
403 	struct netlbl_unlhsh_iface *iface;
404 
405 	iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
406 	if (iface == NULL)
407 		return NULL;
408 
409 	iface->ifindex = ifindex;
410 	INIT_LIST_HEAD(&iface->addr4_list);
411 	INIT_LIST_HEAD(&iface->addr6_list);
412 	iface->valid = 1;
413 	INIT_RCU_HEAD(&iface->rcu);
414 
415 	spin_lock(&netlbl_unlhsh_lock);
416 	if (ifindex > 0) {
417 		bkt = netlbl_unlhsh_hash(ifindex);
418 		if (netlbl_unlhsh_search_iface(ifindex) != NULL)
419 			goto add_iface_failure;
420 		list_add_tail_rcu(&iface->list,
421 				  &rcu_dereference(netlbl_unlhsh)->tbl[bkt]);
422 	} else {
423 		INIT_LIST_HEAD(&iface->list);
424 		if (rcu_dereference(netlbl_unlhsh_def) != NULL)
425 			goto add_iface_failure;
426 		rcu_assign_pointer(netlbl_unlhsh_def, iface);
427 	}
428 	spin_unlock(&netlbl_unlhsh_lock);
429 
430 	return iface;
431 
432 add_iface_failure:
433 	spin_unlock(&netlbl_unlhsh_lock);
434 	kfree(iface);
435 	return NULL;
436 }
437 
438 /**
439  * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
440  * @net: network namespace
441  * @dev_name: interface name
442  * @addr: IP address in network byte order
443  * @mask: address mask in network byte order
444  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
445  * @secid: LSM secid value for the entry
446  * @audit_info: NetLabel audit information
447  *
448  * Description:
449  * Adds a new entry to the unlabeled connection hash table.  Returns zero on
450  * success, negative values on failure.
451  *
452  */
453 int netlbl_unlhsh_add(struct net *net,
454 		      const char *dev_name,
455 		      const void *addr,
456 		      const void *mask,
457 		      u32 addr_len,
458 		      u32 secid,
459 		      struct netlbl_audit *audit_info)
460 {
461 	int ret_val;
462 	int ifindex;
463 	struct net_device *dev;
464 	struct netlbl_unlhsh_iface *iface;
465 	struct audit_buffer *audit_buf = NULL;
466 	char *secctx = NULL;
467 	u32 secctx_len;
468 
469 	if (addr_len != sizeof(struct in_addr) &&
470 	    addr_len != sizeof(struct in6_addr))
471 		return -EINVAL;
472 
473 	rcu_read_lock();
474 	if (dev_name != NULL) {
475 		dev = dev_get_by_name_rcu(net, dev_name);
476 		if (dev == NULL) {
477 			ret_val = -ENODEV;
478 			goto unlhsh_add_return;
479 		}
480 		ifindex = dev->ifindex;
481 		iface = netlbl_unlhsh_search_iface(ifindex);
482 	} else {
483 		ifindex = 0;
484 		iface = rcu_dereference(netlbl_unlhsh_def);
485 	}
486 	if (iface == NULL) {
487 		iface = netlbl_unlhsh_add_iface(ifindex);
488 		if (iface == NULL) {
489 			ret_val = -ENOMEM;
490 			goto unlhsh_add_return;
491 		}
492 	}
493 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
494 					      audit_info);
495 	switch (addr_len) {
496 	case sizeof(struct in_addr): {
497 		struct in_addr *addr4, *mask4;
498 
499 		addr4 = (struct in_addr *)addr;
500 		mask4 = (struct in_addr *)mask;
501 		ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
502 		if (audit_buf != NULL)
503 			netlbl_af4list_audit_addr(audit_buf, 1,
504 						  dev_name,
505 						  addr4->s_addr,
506 						  mask4->s_addr);
507 		break;
508 	}
509 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
510 	case sizeof(struct in6_addr): {
511 		struct in6_addr *addr6, *mask6;
512 
513 		addr6 = (struct in6_addr *)addr;
514 		mask6 = (struct in6_addr *)mask;
515 		ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
516 		if (audit_buf != NULL)
517 			netlbl_af6list_audit_addr(audit_buf, 1,
518 						  dev_name,
519 						  addr6, mask6);
520 		break;
521 	}
522 #endif /* IPv6 */
523 	default:
524 		ret_val = -EINVAL;
525 	}
526 	if (ret_val == 0)
527 		atomic_inc(&netlabel_mgmt_protocount);
528 
529 unlhsh_add_return:
530 	rcu_read_unlock();
531 	if (audit_buf != NULL) {
532 		if (security_secid_to_secctx(secid,
533 					     &secctx,
534 					     &secctx_len) == 0) {
535 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
536 			security_release_secctx(secctx, secctx_len);
537 		}
538 		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
539 		audit_log_end(audit_buf);
540 	}
541 	return ret_val;
542 }
543 
544 /**
545  * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
546  * @net: network namespace
547  * @iface: interface entry
548  * @addr: IP address
549  * @mask: IP address mask
550  * @audit_info: NetLabel audit information
551  *
552  * Description:
553  * Remove an IP address entry from the unlabeled connection hash table.
554  * Returns zero on success, negative values on failure.  The caller is
555  * responsible for calling the rcu_read_[un]lock() functions.
556  *
557  */
558 static int netlbl_unlhsh_remove_addr4(struct net *net,
559 				      struct netlbl_unlhsh_iface *iface,
560 				      const struct in_addr *addr,
561 				      const struct in_addr *mask,
562 				      struct netlbl_audit *audit_info)
563 {
564 	struct netlbl_af4list *list_entry;
565 	struct netlbl_unlhsh_addr4 *entry;
566 	struct audit_buffer *audit_buf;
567 	struct net_device *dev;
568 	char *secctx;
569 	u32 secctx_len;
570 
571 	spin_lock(&netlbl_unlhsh_lock);
572 	list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
573 					   &iface->addr4_list);
574 	spin_unlock(&netlbl_unlhsh_lock);
575 	if (list_entry != NULL)
576 		entry = netlbl_unlhsh_addr4_entry(list_entry);
577 	else
578 		entry = NULL;
579 
580 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
581 					      audit_info);
582 	if (audit_buf != NULL) {
583 		dev = dev_get_by_index(net, iface->ifindex);
584 		netlbl_af4list_audit_addr(audit_buf, 1,
585 					  (dev != NULL ? dev->name : NULL),
586 					  addr->s_addr, mask->s_addr);
587 		if (dev != NULL)
588 			dev_put(dev);
589 		if (entry != NULL &&
590 		    security_secid_to_secctx(entry->secid,
591 					     &secctx, &secctx_len) == 0) {
592 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
593 			security_release_secctx(secctx, secctx_len);
594 		}
595 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
596 		audit_log_end(audit_buf);
597 	}
598 
599 	if (entry == NULL)
600 		return -ENOENT;
601 
602 	call_rcu(&entry->rcu, netlbl_unlhsh_free_addr4);
603 	return 0;
604 }
605 
606 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
607 /**
608  * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
609  * @net: network namespace
610  * @iface: interface entry
611  * @addr: IP address
612  * @mask: IP address mask
613  * @audit_info: NetLabel audit information
614  *
615  * Description:
616  * Remove an IP address entry from the unlabeled connection hash table.
617  * Returns zero on success, negative values on failure.  The caller is
618  * responsible for calling the rcu_read_[un]lock() functions.
619  *
620  */
621 static int netlbl_unlhsh_remove_addr6(struct net *net,
622 				      struct netlbl_unlhsh_iface *iface,
623 				      const struct in6_addr *addr,
624 				      const struct in6_addr *mask,
625 				      struct netlbl_audit *audit_info)
626 {
627 	struct netlbl_af6list *list_entry;
628 	struct netlbl_unlhsh_addr6 *entry;
629 	struct audit_buffer *audit_buf;
630 	struct net_device *dev;
631 	char *secctx;
632 	u32 secctx_len;
633 
634 	spin_lock(&netlbl_unlhsh_lock);
635 	list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
636 	spin_unlock(&netlbl_unlhsh_lock);
637 	if (list_entry != NULL)
638 		entry = netlbl_unlhsh_addr6_entry(list_entry);
639 	else
640 		entry = NULL;
641 
642 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
643 					      audit_info);
644 	if (audit_buf != NULL) {
645 		dev = dev_get_by_index(net, iface->ifindex);
646 		netlbl_af6list_audit_addr(audit_buf, 1,
647 					  (dev != NULL ? dev->name : NULL),
648 					  addr, mask);
649 		if (dev != NULL)
650 			dev_put(dev);
651 		if (entry != NULL &&
652 		    security_secid_to_secctx(entry->secid,
653 					     &secctx, &secctx_len) == 0) {
654 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
655 			security_release_secctx(secctx, secctx_len);
656 		}
657 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
658 		audit_log_end(audit_buf);
659 	}
660 
661 	if (entry == NULL)
662 		return -ENOENT;
663 
664 	call_rcu(&entry->rcu, netlbl_unlhsh_free_addr6);
665 	return 0;
666 }
667 #endif /* IPv6 */
668 
669 /**
670  * netlbl_unlhsh_condremove_iface - Remove an interface entry
671  * @iface: the interface entry
672  *
673  * Description:
674  * Remove an interface entry from the unlabeled connection hash table if it is
675  * empty.  An interface entry is considered to be empty if there are no
676  * address entries assigned to it.
677  *
678  */
679 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
680 {
681 	struct netlbl_af4list *iter4;
682 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
683 	struct netlbl_af6list *iter6;
684 #endif /* IPv6 */
685 
686 	spin_lock(&netlbl_unlhsh_lock);
687 	netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
688 		goto unlhsh_condremove_failure;
689 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
690 	netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
691 		goto unlhsh_condremove_failure;
692 #endif /* IPv6 */
693 	iface->valid = 0;
694 	if (iface->ifindex > 0)
695 		list_del_rcu(&iface->list);
696 	else
697 		rcu_assign_pointer(netlbl_unlhsh_def, NULL);
698 	spin_unlock(&netlbl_unlhsh_lock);
699 
700 	call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
701 	return;
702 
703 unlhsh_condremove_failure:
704 	spin_unlock(&netlbl_unlhsh_lock);
705 	return;
706 }
707 
708 /**
709  * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
710  * @net: network namespace
711  * @dev_name: interface name
712  * @addr: IP address in network byte order
713  * @mask: address mask in network byte order
714  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
715  * @audit_info: NetLabel audit information
716  *
717  * Description:
718  * Removes and existing entry from the unlabeled connection hash table.
719  * Returns zero on success, negative values on failure.
720  *
721  */
722 int netlbl_unlhsh_remove(struct net *net,
723 			 const char *dev_name,
724 			 const void *addr,
725 			 const void *mask,
726 			 u32 addr_len,
727 			 struct netlbl_audit *audit_info)
728 {
729 	int ret_val;
730 	struct net_device *dev;
731 	struct netlbl_unlhsh_iface *iface;
732 
733 	if (addr_len != sizeof(struct in_addr) &&
734 	    addr_len != sizeof(struct in6_addr))
735 		return -EINVAL;
736 
737 	rcu_read_lock();
738 	if (dev_name != NULL) {
739 		dev = dev_get_by_name_rcu(net, dev_name);
740 		if (dev == NULL) {
741 			ret_val = -ENODEV;
742 			goto unlhsh_remove_return;
743 		}
744 		iface = netlbl_unlhsh_search_iface(dev->ifindex);
745 	} else
746 		iface = rcu_dereference(netlbl_unlhsh_def);
747 	if (iface == NULL) {
748 		ret_val = -ENOENT;
749 		goto unlhsh_remove_return;
750 	}
751 	switch (addr_len) {
752 	case sizeof(struct in_addr):
753 		ret_val = netlbl_unlhsh_remove_addr4(net,
754 						     iface, addr, mask,
755 						     audit_info);
756 		break;
757 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
758 	case sizeof(struct in6_addr):
759 		ret_val = netlbl_unlhsh_remove_addr6(net,
760 						     iface, addr, mask,
761 						     audit_info);
762 		break;
763 #endif /* IPv6 */
764 	default:
765 		ret_val = -EINVAL;
766 	}
767 	if (ret_val == 0) {
768 		netlbl_unlhsh_condremove_iface(iface);
769 		atomic_dec(&netlabel_mgmt_protocount);
770 	}
771 
772 unlhsh_remove_return:
773 	rcu_read_unlock();
774 	return ret_val;
775 }
776 
777 /*
778  * General Helper Functions
779  */
780 
781 /**
782  * netlbl_unlhsh_netdev_handler - Network device notification handler
783  * @this: notifier block
784  * @event: the event
785  * @ptr: the network device (cast to void)
786  *
787  * Description:
788  * Handle network device events, although at present all we care about is a
789  * network device going away.  In the case of a device going away we clear any
790  * related entries from the unlabeled connection hash table.
791  *
792  */
793 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
794 					unsigned long event,
795 					void *ptr)
796 {
797 	struct net_device *dev = ptr;
798 	struct netlbl_unlhsh_iface *iface = NULL;
799 
800 	if (!net_eq(dev_net(dev), &init_net))
801 		return NOTIFY_DONE;
802 
803 	/* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
804 	if (event == NETDEV_DOWN) {
805 		spin_lock(&netlbl_unlhsh_lock);
806 		iface = netlbl_unlhsh_search_iface(dev->ifindex);
807 		if (iface != NULL && iface->valid) {
808 			iface->valid = 0;
809 			list_del_rcu(&iface->list);
810 		} else
811 			iface = NULL;
812 		spin_unlock(&netlbl_unlhsh_lock);
813 	}
814 
815 	if (iface != NULL)
816 		call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
817 
818 	return NOTIFY_DONE;
819 }
820 
821 /**
822  * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
823  * @value: desired value
824  * @audit_info: NetLabel audit information
825  *
826  * Description:
827  * Set the value of the unlabeled accept flag to @value.
828  *
829  */
830 static void netlbl_unlabel_acceptflg_set(u8 value,
831 					 struct netlbl_audit *audit_info)
832 {
833 	struct audit_buffer *audit_buf;
834 	u8 old_val;
835 
836 	old_val = netlabel_unlabel_acceptflg;
837 	netlabel_unlabel_acceptflg = value;
838 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
839 					      audit_info);
840 	if (audit_buf != NULL) {
841 		audit_log_format(audit_buf,
842 				 " unlbl_accept=%u old=%u", value, old_val);
843 		audit_log_end(audit_buf);
844 	}
845 }
846 
847 /**
848  * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
849  * @info: the Generic NETLINK info block
850  * @addr: the IP address
851  * @mask: the IP address mask
852  * @len: the address length
853  *
854  * Description:
855  * Examine the Generic NETLINK message and extract the IP address information.
856  * Returns zero on success, negative values on failure.
857  *
858  */
859 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
860 				       void **addr,
861 				       void **mask,
862 				       u32 *len)
863 {
864 	u32 addr_len;
865 
866 	if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
867 		addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
868 		if (addr_len != sizeof(struct in_addr) &&
869 		    addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
870 			return -EINVAL;
871 		*len = addr_len;
872 		*addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
873 		*mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
874 		return 0;
875 	} else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
876 		addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
877 		if (addr_len != sizeof(struct in6_addr) &&
878 		    addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
879 			return -EINVAL;
880 		*len = addr_len;
881 		*addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
882 		*mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
883 		return 0;
884 	}
885 
886 	return -EINVAL;
887 }
888 
889 /*
890  * NetLabel Command Handlers
891  */
892 
893 /**
894  * netlbl_unlabel_accept - Handle an ACCEPT message
895  * @skb: the NETLINK buffer
896  * @info: the Generic NETLINK info block
897  *
898  * Description:
899  * Process a user generated ACCEPT message and set the accept flag accordingly.
900  * Returns zero on success, negative values on failure.
901  *
902  */
903 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
904 {
905 	u8 value;
906 	struct netlbl_audit audit_info;
907 
908 	if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
909 		value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
910 		if (value == 1 || value == 0) {
911 			netlbl_netlink_auditinfo(skb, &audit_info);
912 			netlbl_unlabel_acceptflg_set(value, &audit_info);
913 			return 0;
914 		}
915 	}
916 
917 	return -EINVAL;
918 }
919 
920 /**
921  * netlbl_unlabel_list - Handle a LIST message
922  * @skb: the NETLINK buffer
923  * @info: the Generic NETLINK info block
924  *
925  * Description:
926  * Process a user generated LIST message and respond with the current status.
927  * Returns zero on success, negative values on failure.
928  *
929  */
930 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
931 {
932 	int ret_val = -EINVAL;
933 	struct sk_buff *ans_skb;
934 	void *data;
935 
936 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
937 	if (ans_skb == NULL)
938 		goto list_failure;
939 	data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
940 				 0, NLBL_UNLABEL_C_LIST);
941 	if (data == NULL) {
942 		ret_val = -ENOMEM;
943 		goto list_failure;
944 	}
945 
946 	ret_val = nla_put_u8(ans_skb,
947 			     NLBL_UNLABEL_A_ACPTFLG,
948 			     netlabel_unlabel_acceptflg);
949 	if (ret_val != 0)
950 		goto list_failure;
951 
952 	genlmsg_end(ans_skb, data);
953 	return genlmsg_reply(ans_skb, info);
954 
955 list_failure:
956 	kfree_skb(ans_skb);
957 	return ret_val;
958 }
959 
960 /**
961  * netlbl_unlabel_staticadd - Handle a STATICADD message
962  * @skb: the NETLINK buffer
963  * @info: the Generic NETLINK info block
964  *
965  * Description:
966  * Process a user generated STATICADD message and add a new unlabeled
967  * connection entry to the hash table.  Returns zero on success, negative
968  * values on failure.
969  *
970  */
971 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
972 				    struct genl_info *info)
973 {
974 	int ret_val;
975 	char *dev_name;
976 	void *addr;
977 	void *mask;
978 	u32 addr_len;
979 	u32 secid;
980 	struct netlbl_audit audit_info;
981 
982 	/* Don't allow users to add both IPv4 and IPv6 addresses for a
983 	 * single entry.  However, allow users to create two entries, one each
984 	 * for IPv4 and IPv4, with the same LSM security context which should
985 	 * achieve the same result. */
986 	if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
987 	    !info->attrs[NLBL_UNLABEL_A_IFACE] ||
988 	    !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
989 	       !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
990 	      (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
991 	       !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
992 		return -EINVAL;
993 
994 	netlbl_netlink_auditinfo(skb, &audit_info);
995 
996 	ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
997 	if (ret_val != 0)
998 		return ret_val;
999 	dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1000 	ret_val = security_secctx_to_secid(
1001 		                  nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1002 				  nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1003 				  &secid);
1004 	if (ret_val != 0)
1005 		return ret_val;
1006 
1007 	return netlbl_unlhsh_add(&init_net,
1008 				 dev_name, addr, mask, addr_len, secid,
1009 				 &audit_info);
1010 }
1011 
1012 /**
1013  * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
1014  * @skb: the NETLINK buffer
1015  * @info: the Generic NETLINK info block
1016  *
1017  * Description:
1018  * Process a user generated STATICADDDEF message and add a new default
1019  * unlabeled connection entry.  Returns zero on success, negative values on
1020  * failure.
1021  *
1022  */
1023 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
1024 				       struct genl_info *info)
1025 {
1026 	int ret_val;
1027 	void *addr;
1028 	void *mask;
1029 	u32 addr_len;
1030 	u32 secid;
1031 	struct netlbl_audit audit_info;
1032 
1033 	/* Don't allow users to add both IPv4 and IPv6 addresses for a
1034 	 * single entry.  However, allow users to create two entries, one each
1035 	 * for IPv4 and IPv6, with the same LSM security context which should
1036 	 * achieve the same result. */
1037 	if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
1038 	    !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1039 	       !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1040 	      (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1041 	       !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1042 		return -EINVAL;
1043 
1044 	netlbl_netlink_auditinfo(skb, &audit_info);
1045 
1046 	ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1047 	if (ret_val != 0)
1048 		return ret_val;
1049 	ret_val = security_secctx_to_secid(
1050 		                  nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1051 				  nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1052 				  &secid);
1053 	if (ret_val != 0)
1054 		return ret_val;
1055 
1056 	return netlbl_unlhsh_add(&init_net,
1057 				 NULL, addr, mask, addr_len, secid,
1058 				 &audit_info);
1059 }
1060 
1061 /**
1062  * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
1063  * @skb: the NETLINK buffer
1064  * @info: the Generic NETLINK info block
1065  *
1066  * Description:
1067  * Process a user generated STATICREMOVE message and remove the specified
1068  * unlabeled connection entry.  Returns zero on success, negative values on
1069  * failure.
1070  *
1071  */
1072 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
1073 				       struct genl_info *info)
1074 {
1075 	int ret_val;
1076 	char *dev_name;
1077 	void *addr;
1078 	void *mask;
1079 	u32 addr_len;
1080 	struct netlbl_audit audit_info;
1081 
1082 	/* See the note in netlbl_unlabel_staticadd() about not allowing both
1083 	 * IPv4 and IPv6 in the same entry. */
1084 	if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1085 	    !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1086 	       !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1087 	      (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1088 	       !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1089 		return -EINVAL;
1090 
1091 	netlbl_netlink_auditinfo(skb, &audit_info);
1092 
1093 	ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1094 	if (ret_val != 0)
1095 		return ret_val;
1096 	dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1097 
1098 	return netlbl_unlhsh_remove(&init_net,
1099 				    dev_name, addr, mask, addr_len,
1100 				    &audit_info);
1101 }
1102 
1103 /**
1104  * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1105  * @skb: the NETLINK buffer
1106  * @info: the Generic NETLINK info block
1107  *
1108  * Description:
1109  * Process a user generated STATICREMOVEDEF message and remove the default
1110  * unlabeled connection entry.  Returns zero on success, negative values on
1111  * failure.
1112  *
1113  */
1114 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1115 					  struct genl_info *info)
1116 {
1117 	int ret_val;
1118 	void *addr;
1119 	void *mask;
1120 	u32 addr_len;
1121 	struct netlbl_audit audit_info;
1122 
1123 	/* See the note in netlbl_unlabel_staticadd() about not allowing both
1124 	 * IPv4 and IPv6 in the same entry. */
1125 	if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1126 	       !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1127 	      (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1128 	       !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1129 		return -EINVAL;
1130 
1131 	netlbl_netlink_auditinfo(skb, &audit_info);
1132 
1133 	ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1134 	if (ret_val != 0)
1135 		return ret_val;
1136 
1137 	return netlbl_unlhsh_remove(&init_net,
1138 				    NULL, addr, mask, addr_len,
1139 				    &audit_info);
1140 }
1141 
1142 
1143 /**
1144  * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1145  * @cmd: command/message
1146  * @iface: the interface entry
1147  * @addr4: the IPv4 address entry
1148  * @addr6: the IPv6 address entry
1149  * @arg: the netlbl_unlhsh_walk_arg structure
1150  *
1151  * Description:
1152  * This function is designed to be used to generate a response for a
1153  * STATICLIST or STATICLISTDEF message.  When called either @addr4 or @addr6
1154  * can be specified, not both, the other unspecified entry should be set to
1155  * NULL by the caller.  Returns the size of the message on success, negative
1156  * values on failure.
1157  *
1158  */
1159 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1160 				       const struct netlbl_unlhsh_iface *iface,
1161 				       const struct netlbl_unlhsh_addr4 *addr4,
1162 				       const struct netlbl_unlhsh_addr6 *addr6,
1163 				       void *arg)
1164 {
1165 	int ret_val = -ENOMEM;
1166 	struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1167 	struct net_device *dev;
1168 	void *data;
1169 	u32 secid;
1170 	char *secctx;
1171 	u32 secctx_len;
1172 
1173 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
1174 			   cb_arg->seq, &netlbl_unlabel_gnl_family,
1175 			   NLM_F_MULTI, cmd);
1176 	if (data == NULL)
1177 		goto list_cb_failure;
1178 
1179 	if (iface->ifindex > 0) {
1180 		dev = dev_get_by_index(&init_net, iface->ifindex);
1181 		if (!dev) {
1182 			ret_val = -ENODEV;
1183 			goto list_cb_failure;
1184 		}
1185 		ret_val = nla_put_string(cb_arg->skb,
1186 					 NLBL_UNLABEL_A_IFACE, dev->name);
1187 		dev_put(dev);
1188 		if (ret_val != 0)
1189 			goto list_cb_failure;
1190 	}
1191 
1192 	if (addr4) {
1193 		struct in_addr addr_struct;
1194 
1195 		addr_struct.s_addr = addr4->list.addr;
1196 		ret_val = nla_put(cb_arg->skb,
1197 				  NLBL_UNLABEL_A_IPV4ADDR,
1198 				  sizeof(struct in_addr),
1199 				  &addr_struct);
1200 		if (ret_val != 0)
1201 			goto list_cb_failure;
1202 
1203 		addr_struct.s_addr = addr4->list.mask;
1204 		ret_val = nla_put(cb_arg->skb,
1205 				  NLBL_UNLABEL_A_IPV4MASK,
1206 				  sizeof(struct in_addr),
1207 				  &addr_struct);
1208 		if (ret_val != 0)
1209 			goto list_cb_failure;
1210 
1211 		secid = addr4->secid;
1212 	} else {
1213 		ret_val = nla_put(cb_arg->skb,
1214 				  NLBL_UNLABEL_A_IPV6ADDR,
1215 				  sizeof(struct in6_addr),
1216 				  &addr6->list.addr);
1217 		if (ret_val != 0)
1218 			goto list_cb_failure;
1219 
1220 		ret_val = nla_put(cb_arg->skb,
1221 				  NLBL_UNLABEL_A_IPV6MASK,
1222 				  sizeof(struct in6_addr),
1223 				  &addr6->list.mask);
1224 		if (ret_val != 0)
1225 			goto list_cb_failure;
1226 
1227 		secid = addr6->secid;
1228 	}
1229 
1230 	ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1231 	if (ret_val != 0)
1232 		goto list_cb_failure;
1233 	ret_val = nla_put(cb_arg->skb,
1234 			  NLBL_UNLABEL_A_SECCTX,
1235 			  secctx_len,
1236 			  secctx);
1237 	security_release_secctx(secctx, secctx_len);
1238 	if (ret_val != 0)
1239 		goto list_cb_failure;
1240 
1241 	cb_arg->seq++;
1242 	return genlmsg_end(cb_arg->skb, data);
1243 
1244 list_cb_failure:
1245 	genlmsg_cancel(cb_arg->skb, data);
1246 	return ret_val;
1247 }
1248 
1249 /**
1250  * netlbl_unlabel_staticlist - Handle a STATICLIST message
1251  * @skb: the NETLINK buffer
1252  * @cb: the NETLINK callback
1253  *
1254  * Description:
1255  * Process a user generated STATICLIST message and dump the unlabeled
1256  * connection hash table in a form suitable for use in a kernel generated
1257  * STATICLIST message.  Returns the length of @skb.
1258  *
1259  */
1260 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1261 				     struct netlink_callback *cb)
1262 {
1263 	struct netlbl_unlhsh_walk_arg cb_arg;
1264 	u32 skip_bkt = cb->args[0];
1265 	u32 skip_chain = cb->args[1];
1266 	u32 skip_addr4 = cb->args[2];
1267 	u32 skip_addr6 = cb->args[3];
1268 	u32 iter_bkt;
1269 	u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1270 	struct netlbl_unlhsh_iface *iface;
1271 	struct list_head *iter_list;
1272 	struct netlbl_af4list *addr4;
1273 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1274 	struct netlbl_af6list *addr6;
1275 #endif
1276 
1277 	cb_arg.nl_cb = cb;
1278 	cb_arg.skb = skb;
1279 	cb_arg.seq = cb->nlh->nlmsg_seq;
1280 
1281 	rcu_read_lock();
1282 	for (iter_bkt = skip_bkt;
1283 	     iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1284 	     iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1285 		iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1286 		list_for_each_entry_rcu(iface, iter_list, list) {
1287 			if (!iface->valid ||
1288 			    iter_chain++ < skip_chain)
1289 				continue;
1290 			netlbl_af4list_foreach_rcu(addr4,
1291 						   &iface->addr4_list) {
1292 				if (iter_addr4++ < skip_addr4)
1293 					continue;
1294 				if (netlbl_unlabel_staticlist_gen(
1295 					      NLBL_UNLABEL_C_STATICLIST,
1296 					      iface,
1297 					      netlbl_unlhsh_addr4_entry(addr4),
1298 					      NULL,
1299 					      &cb_arg) < 0) {
1300 					iter_addr4--;
1301 					iter_chain--;
1302 					goto unlabel_staticlist_return;
1303 				}
1304 			}
1305 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1306 			netlbl_af6list_foreach_rcu(addr6,
1307 						   &iface->addr6_list) {
1308 				if (iter_addr6++ < skip_addr6)
1309 					continue;
1310 				if (netlbl_unlabel_staticlist_gen(
1311 					      NLBL_UNLABEL_C_STATICLIST,
1312 					      iface,
1313 					      NULL,
1314 					      netlbl_unlhsh_addr6_entry(addr6),
1315 					      &cb_arg) < 0) {
1316 					iter_addr6--;
1317 					iter_chain--;
1318 					goto unlabel_staticlist_return;
1319 				}
1320 			}
1321 #endif /* IPv6 */
1322 		}
1323 	}
1324 
1325 unlabel_staticlist_return:
1326 	rcu_read_unlock();
1327 	cb->args[0] = skip_bkt;
1328 	cb->args[1] = skip_chain;
1329 	cb->args[2] = skip_addr4;
1330 	cb->args[3] = skip_addr6;
1331 	return skb->len;
1332 }
1333 
1334 /**
1335  * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1336  * @skb: the NETLINK buffer
1337  * @cb: the NETLINK callback
1338  *
1339  * Description:
1340  * Process a user generated STATICLISTDEF message and dump the default
1341  * unlabeled connection entry in a form suitable for use in a kernel generated
1342  * STATICLISTDEF message.  Returns the length of @skb.
1343  *
1344  */
1345 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1346 					struct netlink_callback *cb)
1347 {
1348 	struct netlbl_unlhsh_walk_arg cb_arg;
1349 	struct netlbl_unlhsh_iface *iface;
1350 	u32 skip_addr4 = cb->args[0];
1351 	u32 skip_addr6 = cb->args[1];
1352 	u32 iter_addr4 = 0;
1353 	struct netlbl_af4list *addr4;
1354 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1355 	u32 iter_addr6 = 0;
1356 	struct netlbl_af6list *addr6;
1357 #endif
1358 
1359 	cb_arg.nl_cb = cb;
1360 	cb_arg.skb = skb;
1361 	cb_arg.seq = cb->nlh->nlmsg_seq;
1362 
1363 	rcu_read_lock();
1364 	iface = rcu_dereference(netlbl_unlhsh_def);
1365 	if (iface == NULL || !iface->valid)
1366 		goto unlabel_staticlistdef_return;
1367 
1368 	netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1369 		if (iter_addr4++ < skip_addr4)
1370 			continue;
1371 		if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1372 					      iface,
1373 					      netlbl_unlhsh_addr4_entry(addr4),
1374 					      NULL,
1375 					      &cb_arg) < 0) {
1376 			iter_addr4--;
1377 			goto unlabel_staticlistdef_return;
1378 		}
1379 	}
1380 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1381 	netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1382 		if (iter_addr6++ < skip_addr6)
1383 			continue;
1384 		if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1385 					      iface,
1386 					      NULL,
1387 					      netlbl_unlhsh_addr6_entry(addr6),
1388 					      &cb_arg) < 0) {
1389 			iter_addr6--;
1390 			goto unlabel_staticlistdef_return;
1391 		}
1392 	}
1393 #endif /* IPv6 */
1394 
1395 unlabel_staticlistdef_return:
1396 	rcu_read_unlock();
1397 	cb->args[0] = skip_addr4;
1398 	cb->args[1] = skip_addr6;
1399 	return skb->len;
1400 }
1401 
1402 /*
1403  * NetLabel Generic NETLINK Command Definitions
1404  */
1405 
1406 static struct genl_ops netlbl_unlabel_genl_ops[] = {
1407 	{
1408 	.cmd = NLBL_UNLABEL_C_STATICADD,
1409 	.flags = GENL_ADMIN_PERM,
1410 	.policy = netlbl_unlabel_genl_policy,
1411 	.doit = netlbl_unlabel_staticadd,
1412 	.dumpit = NULL,
1413 	},
1414 	{
1415 	.cmd = NLBL_UNLABEL_C_STATICREMOVE,
1416 	.flags = GENL_ADMIN_PERM,
1417 	.policy = netlbl_unlabel_genl_policy,
1418 	.doit = netlbl_unlabel_staticremove,
1419 	.dumpit = NULL,
1420 	},
1421 	{
1422 	.cmd = NLBL_UNLABEL_C_STATICLIST,
1423 	.flags = 0,
1424 	.policy = netlbl_unlabel_genl_policy,
1425 	.doit = NULL,
1426 	.dumpit = netlbl_unlabel_staticlist,
1427 	},
1428 	{
1429 	.cmd = NLBL_UNLABEL_C_STATICADDDEF,
1430 	.flags = GENL_ADMIN_PERM,
1431 	.policy = netlbl_unlabel_genl_policy,
1432 	.doit = netlbl_unlabel_staticadddef,
1433 	.dumpit = NULL,
1434 	},
1435 	{
1436 	.cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1437 	.flags = GENL_ADMIN_PERM,
1438 	.policy = netlbl_unlabel_genl_policy,
1439 	.doit = netlbl_unlabel_staticremovedef,
1440 	.dumpit = NULL,
1441 	},
1442 	{
1443 	.cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1444 	.flags = 0,
1445 	.policy = netlbl_unlabel_genl_policy,
1446 	.doit = NULL,
1447 	.dumpit = netlbl_unlabel_staticlistdef,
1448 	},
1449 	{
1450 	.cmd = NLBL_UNLABEL_C_ACCEPT,
1451 	.flags = GENL_ADMIN_PERM,
1452 	.policy = netlbl_unlabel_genl_policy,
1453 	.doit = netlbl_unlabel_accept,
1454 	.dumpit = NULL,
1455 	},
1456 	{
1457 	.cmd = NLBL_UNLABEL_C_LIST,
1458 	.flags = 0,
1459 	.policy = netlbl_unlabel_genl_policy,
1460 	.doit = netlbl_unlabel_list,
1461 	.dumpit = NULL,
1462 	},
1463 };
1464 
1465 /*
1466  * NetLabel Generic NETLINK Protocol Functions
1467  */
1468 
1469 /**
1470  * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1471  *
1472  * Description:
1473  * Register the unlabeled packet NetLabel component with the Generic NETLINK
1474  * mechanism.  Returns zero on success, negative values on failure.
1475  *
1476  */
1477 int __init netlbl_unlabel_genl_init(void)
1478 {
1479 	return genl_register_family_with_ops(&netlbl_unlabel_gnl_family,
1480 		netlbl_unlabel_genl_ops, ARRAY_SIZE(netlbl_unlabel_genl_ops));
1481 }
1482 
1483 /*
1484  * NetLabel KAPI Hooks
1485  */
1486 
1487 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1488 	.notifier_call = netlbl_unlhsh_netdev_handler,
1489 };
1490 
1491 /**
1492  * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1493  * @size: the number of bits to use for the hash buckets
1494  *
1495  * Description:
1496  * Initializes the unlabeled connection hash table and registers a network
1497  * device notification handler.  This function should only be called by the
1498  * NetLabel subsystem itself during initialization.  Returns zero on success,
1499  * non-zero values on error.
1500  *
1501  */
1502 int __init netlbl_unlabel_init(u32 size)
1503 {
1504 	u32 iter;
1505 	struct netlbl_unlhsh_tbl *hsh_tbl;
1506 
1507 	if (size == 0)
1508 		return -EINVAL;
1509 
1510 	hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1511 	if (hsh_tbl == NULL)
1512 		return -ENOMEM;
1513 	hsh_tbl->size = 1 << size;
1514 	hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1515 			       sizeof(struct list_head),
1516 			       GFP_KERNEL);
1517 	if (hsh_tbl->tbl == NULL) {
1518 		kfree(hsh_tbl);
1519 		return -ENOMEM;
1520 	}
1521 	for (iter = 0; iter < hsh_tbl->size; iter++)
1522 		INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1523 
1524 	rcu_read_lock();
1525 	spin_lock(&netlbl_unlhsh_lock);
1526 	rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1527 	spin_unlock(&netlbl_unlhsh_lock);
1528 	rcu_read_unlock();
1529 
1530 	register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1531 
1532 	return 0;
1533 }
1534 
1535 /**
1536  * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1537  * @skb: the packet
1538  * @family: protocol family
1539  * @secattr: the security attributes
1540  *
1541  * Description:
1542  * Determine the security attributes, if any, for an unlabled packet and return
1543  * them in @secattr.  Returns zero on success and negative values on failure.
1544  *
1545  */
1546 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1547 			   u16 family,
1548 			   struct netlbl_lsm_secattr *secattr)
1549 {
1550 	struct netlbl_unlhsh_iface *iface;
1551 
1552 	rcu_read_lock();
1553 	iface = netlbl_unlhsh_search_iface_def(skb->skb_iif);
1554 	if (iface == NULL)
1555 		goto unlabel_getattr_nolabel;
1556 	switch (family) {
1557 	case PF_INET: {
1558 		struct iphdr *hdr4;
1559 		struct netlbl_af4list *addr4;
1560 
1561 		hdr4 = ip_hdr(skb);
1562 		addr4 = netlbl_af4list_search(hdr4->saddr,
1563 					      &iface->addr4_list);
1564 		if (addr4 == NULL)
1565 			goto unlabel_getattr_nolabel;
1566 		secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1567 		break;
1568 	}
1569 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1570 	case PF_INET6: {
1571 		struct ipv6hdr *hdr6;
1572 		struct netlbl_af6list *addr6;
1573 
1574 		hdr6 = ipv6_hdr(skb);
1575 		addr6 = netlbl_af6list_search(&hdr6->saddr,
1576 					      &iface->addr6_list);
1577 		if (addr6 == NULL)
1578 			goto unlabel_getattr_nolabel;
1579 		secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1580 		break;
1581 	}
1582 #endif /* IPv6 */
1583 	default:
1584 		goto unlabel_getattr_nolabel;
1585 	}
1586 	rcu_read_unlock();
1587 
1588 	secattr->flags |= NETLBL_SECATTR_SECID;
1589 	secattr->type = NETLBL_NLTYPE_UNLABELED;
1590 	return 0;
1591 
1592 unlabel_getattr_nolabel:
1593 	rcu_read_unlock();
1594 	if (netlabel_unlabel_acceptflg == 0)
1595 		return -ENOMSG;
1596 	secattr->type = NETLBL_NLTYPE_UNLABELED;
1597 	return 0;
1598 }
1599 
1600 /**
1601  * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1602  *
1603  * Description:
1604  * Set the default NetLabel configuration to allow incoming unlabeled packets
1605  * and to send unlabeled network traffic by default.
1606  *
1607  */
1608 int __init netlbl_unlabel_defconf(void)
1609 {
1610 	int ret_val;
1611 	struct netlbl_dom_map *entry;
1612 	struct netlbl_audit audit_info;
1613 
1614 	/* Only the kernel is allowed to call this function and the only time
1615 	 * it is called is at bootup before the audit subsystem is reporting
1616 	 * messages so don't worry to much about these values. */
1617 	security_task_getsecid(current, &audit_info.secid);
1618 	audit_info.loginuid = 0;
1619 	audit_info.sessionid = 0;
1620 
1621 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1622 	if (entry == NULL)
1623 		return -ENOMEM;
1624 	entry->type = NETLBL_NLTYPE_UNLABELED;
1625 	ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1626 	if (ret_val != 0)
1627 		return ret_val;
1628 
1629 	netlbl_unlabel_acceptflg_set(1, &audit_info);
1630 
1631 	return 0;
1632 }
1633