xref: /linux/include/net/netlabel.h (revision ceba1832b1b2da0149c51de62a847c00bca1677a)
1 /*
2  * NetLabel System
3  *
4  * The NetLabel system manages static and dynamic label mappings for network
5  * protocols such as CIPSO and RIPSO.
6  *
7  * Author: Paul Moore <paul@paul-moore.com>
8  *
9  */
10 
11 /*
12  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008
13  *
14  * This program is free software;  you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
22  * the GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program;  if not, see <http://www.gnu.org/licenses/>.
26  *
27  */
28 
29 #ifndef _NETLABEL_H
30 #define _NETLABEL_H
31 
32 #include <linux/types.h>
33 #include <linux/slab.h>
34 #include <linux/net.h>
35 #include <linux/skbuff.h>
36 #include <linux/in.h>
37 #include <linux/in6.h>
38 #include <net/netlink.h>
39 #include <net/request_sock.h>
40 #include <linux/atomic.h>
41 
42 struct cipso_v4_doi;
43 struct calipso_doi;
44 
45 /*
46  * NetLabel - A management interface for maintaining network packet label
47  *            mapping tables for explicit packet labling protocols.
48  *
49  * Network protocols such as CIPSO and RIPSO require a label translation layer
50  * to convert the label on the packet into something meaningful on the host
51  * machine.  In the current Linux implementation these mapping tables live
52  * inside the kernel; NetLabel provides a mechanism for user space applications
53  * to manage these mapping tables.
54  *
55  * NetLabel makes use of the Generic NETLINK mechanism as a transport layer to
56  * send messages between kernel and user space.  The general format of a
57  * NetLabel message is shown below:
58  *
59  *  +-----------------+-------------------+--------- --- -- -
60  *  | struct nlmsghdr | struct genlmsghdr | payload
61  *  +-----------------+-------------------+--------- --- -- -
62  *
63  * The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal.
64  * The payload is dependent on the subsystem specified in the
65  * 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions
66  * should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c
67  * file.  All of the fields in the NetLabel payload are NETLINK attributes, see
68  * the include/net/netlink.h file for more information on NETLINK attributes.
69  *
70  */
71 
72 /*
73  * NetLabel NETLINK protocol
74  */
75 
76 /* NetLabel NETLINK protocol version
77  *  1: initial version
78  *  2: added static labels for unlabeled connections
79  *  3: network selectors added to the NetLabel/LSM domain mapping and the
80  *     CIPSO_V4_MAP_LOCAL CIPSO mapping was added
81  */
82 #define NETLBL_PROTO_VERSION            3
83 
84 /* NetLabel NETLINK types/families */
85 #define NETLBL_NLTYPE_NONE              0
86 #define NETLBL_NLTYPE_MGMT              1
87 #define NETLBL_NLTYPE_MGMT_NAME         "NLBL_MGMT"
88 #define NETLBL_NLTYPE_RIPSO             2
89 #define NETLBL_NLTYPE_RIPSO_NAME        "NLBL_RIPSO"
90 #define NETLBL_NLTYPE_CIPSOV4           3
91 #define NETLBL_NLTYPE_CIPSOV4_NAME      "NLBL_CIPSOv4"
92 #define NETLBL_NLTYPE_CIPSOV6           4
93 #define NETLBL_NLTYPE_CIPSOV6_NAME      "NLBL_CIPSOv6"
94 #define NETLBL_NLTYPE_UNLABELED         5
95 #define NETLBL_NLTYPE_UNLABELED_NAME    "NLBL_UNLBL"
96 #define NETLBL_NLTYPE_ADDRSELECT        6
97 #define NETLBL_NLTYPE_ADDRSELECT_NAME   "NLBL_ADRSEL"
98 #define NETLBL_NLTYPE_CALIPSO           7
99 #define NETLBL_NLTYPE_CALIPSO_NAME      "NLBL_CALIPSO"
100 
101 /*
102  * NetLabel - Kernel API for accessing the network packet label mappings.
103  *
104  * The following functions are provided for use by other kernel modules,
105  * specifically kernel LSM modules, to provide a consistent, transparent API
106  * for dealing with explicit packet labeling protocols such as CIPSO and
107  * RIPSO.  The functions defined here are implemented in the
108  * net/netlabel/netlabel_kapi.c file.
109  *
110  */
111 
112 /* NetLabel audit information */
113 struct netlbl_audit {
114 	u32 secid;
115 	kuid_t loginuid;
116 	unsigned int sessionid;
117 };
118 
119 /*
120  * LSM security attributes
121  */
122 
123 /**
124  * struct netlbl_lsm_cache - NetLabel LSM security attribute cache
125  * @refcount: atomic reference counter
126  * @free: LSM supplied function to free the cache data
127  * @data: LSM supplied cache data
128  *
129  * Description:
130  * This structure is provided for LSMs which wish to make use of the NetLabel
131  * caching mechanism to store LSM specific data/attributes in the NetLabel
132  * cache.  If the LSM has to perform a lot of translation from the NetLabel
133  * security attributes into it's own internal representation then the cache
134  * mechanism can provide a way to eliminate some or all of that translation
135  * overhead on a cache hit.
136  *
137  */
138 struct netlbl_lsm_cache {
139 	atomic_t refcount;
140 	void (*free) (const void *data);
141 	void *data;
142 };
143 
144 /**
145  * struct netlbl_lsm_catmap - NetLabel LSM secattr category bitmap
146  * @startbit: the value of the lowest order bit in the bitmap
147  * @bitmap: the category bitmap
148  * @next: pointer to the next bitmap "node" or NULL
149  *
150  * Description:
151  * This structure is used to represent category bitmaps.  Due to the large
152  * number of categories supported by most labeling protocols it is not
153  * practical to transfer a full bitmap internally so NetLabel adopts a sparse
154  * bitmap structure modeled after SELinux's ebitmap structure.
155  * The catmap bitmap field MUST be a power of two in length and large
156  * enough to hold at least 240 bits.  Special care (i.e. check the code!)
157  * should be used when changing these values as the LSM implementation
158  * probably has functions which rely on the sizes of these types to speed
159  * processing.
160  *
161  */
162 #define NETLBL_CATMAP_MAPTYPE           u64
163 #define NETLBL_CATMAP_MAPCNT            4
164 #define NETLBL_CATMAP_MAPSIZE           (sizeof(NETLBL_CATMAP_MAPTYPE) * 8)
165 #define NETLBL_CATMAP_SIZE              (NETLBL_CATMAP_MAPSIZE * \
166 					 NETLBL_CATMAP_MAPCNT)
167 #define NETLBL_CATMAP_BIT               (NETLBL_CATMAP_MAPTYPE)0x01
168 struct netlbl_lsm_catmap {
169 	u32 startbit;
170 	NETLBL_CATMAP_MAPTYPE bitmap[NETLBL_CATMAP_MAPCNT];
171 	struct netlbl_lsm_catmap *next;
172 };
173 
174 /**
175  * struct netlbl_lsm_secattr - NetLabel LSM security attributes
176  * @flags: indicate structure attributes, see NETLBL_SECATTR_*
177  * @type: indicate the NLTYPE of the attributes
178  * @domain: the NetLabel LSM domain
179  * @cache: NetLabel LSM specific cache
180  * @attr.mls: MLS sensitivity label
181  * @attr.mls.cat: MLS category bitmap
182  * @attr.mls.lvl: MLS sensitivity level
183  * @attr.secid: LSM specific secid token
184  *
185  * Description:
186  * This structure is used to pass security attributes between NetLabel and the
187  * LSM modules.  The flags field is used to specify which fields within the
188  * struct are valid and valid values can be created by bitwise OR'ing the
189  * NETLBL_SECATTR_* defines.  The domain field is typically set by the LSM to
190  * specify domain specific configuration settings and is not usually used by
191  * NetLabel itself when returning security attributes to the LSM.
192  *
193  */
194 struct netlbl_lsm_secattr {
195 	u32 flags;
196 	/* bitmap values for 'flags' */
197 #define NETLBL_SECATTR_NONE             0x00000000
198 #define NETLBL_SECATTR_DOMAIN           0x00000001
199 #define NETLBL_SECATTR_DOMAIN_CPY       (NETLBL_SECATTR_DOMAIN | \
200 					 NETLBL_SECATTR_FREE_DOMAIN)
201 #define NETLBL_SECATTR_CACHE            0x00000002
202 #define NETLBL_SECATTR_MLS_LVL          0x00000004
203 #define NETLBL_SECATTR_MLS_CAT          0x00000008
204 #define NETLBL_SECATTR_SECID            0x00000010
205 	/* bitmap meta-values for 'flags' */
206 #define NETLBL_SECATTR_FREE_DOMAIN      0x01000000
207 #define NETLBL_SECATTR_CACHEABLE        (NETLBL_SECATTR_MLS_LVL | \
208 					 NETLBL_SECATTR_MLS_CAT | \
209 					 NETLBL_SECATTR_SECID)
210 	u32 type;
211 	char *domain;
212 	struct netlbl_lsm_cache *cache;
213 	struct {
214 		struct {
215 			struct netlbl_lsm_catmap *cat;
216 			u32 lvl;
217 		} mls;
218 		u32 secid;
219 	} attr;
220 };
221 
222 /**
223  * struct netlbl_calipso_ops - NetLabel CALIPSO operations
224  * @doi_add: add a CALIPSO DOI
225  * @doi_free: free a CALIPSO DOI
226  * @doi_getdef: returns a reference to a DOI
227  * @doi_putdef: releases a reference of a DOI
228  * @doi_walk: enumerate the DOI list
229  * @sock_getattr: retrieve the socket's attr
230  * @sock_setattr: set the socket's attr
231  * @sock_delattr: remove the socket's attr
232  *
233  * Description:
234  * This structure is filled out by the CALIPSO engine and passed
235  * to the NetLabel core via a call to netlbl_calipso_ops_register().
236  * It enables the CALIPSO engine (and hence IPv6) to be compiled
237  * as a module.
238  */
239 struct netlbl_calipso_ops {
240 	int (*doi_add)(struct calipso_doi *doi_def,
241 		       struct netlbl_audit *audit_info);
242 	void (*doi_free)(struct calipso_doi *doi_def);
243 	int (*doi_remove)(u32 doi, struct netlbl_audit *audit_info);
244 	struct calipso_doi *(*doi_getdef)(u32 doi);
245 	void (*doi_putdef)(struct calipso_doi *doi_def);
246 	int (*doi_walk)(u32 *skip_cnt,
247 			int (*callback)(struct calipso_doi *doi_def, void *arg),
248 			void *cb_arg);
249 	int (*sock_getattr)(struct sock *sk,
250 			    struct netlbl_lsm_secattr *secattr);
251 	int (*sock_setattr)(struct sock *sk,
252 			    const struct calipso_doi *doi_def,
253 			    const struct netlbl_lsm_secattr *secattr);
254 	void (*sock_delattr)(struct sock *sk);
255 };
256 
257 /*
258  * LSM security attribute operations (inline)
259  */
260 
261 /**
262  * netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache
263  * @flags: the memory allocation flags
264  *
265  * Description:
266  * Allocate and initialize a netlbl_lsm_cache structure.  Returns a pointer
267  * on success, NULL on failure.
268  *
269  */
270 static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags)
271 {
272 	struct netlbl_lsm_cache *cache;
273 
274 	cache = kzalloc(sizeof(*cache), flags);
275 	if (cache)
276 		atomic_set(&cache->refcount, 1);
277 	return cache;
278 }
279 
280 /**
281  * netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct
282  * @cache: the struct to free
283  *
284  * Description:
285  * Frees @secattr including all of the internal buffers.
286  *
287  */
288 static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache)
289 {
290 	if (!atomic_dec_and_test(&cache->refcount))
291 		return;
292 
293 	if (cache->free)
294 		cache->free(cache->data);
295 	kfree(cache);
296 }
297 
298 /**
299  * netlbl_catmap_alloc - Allocate a LSM secattr catmap
300  * @flags: memory allocation flags
301  *
302  * Description:
303  * Allocate memory for a LSM secattr catmap, returns a pointer on success, NULL
304  * on failure.
305  *
306  */
307 static inline struct netlbl_lsm_catmap *netlbl_catmap_alloc(gfp_t flags)
308 {
309 	return kzalloc(sizeof(struct netlbl_lsm_catmap), flags);
310 }
311 
312 /**
313  * netlbl_catmap_free - Free a LSM secattr catmap
314  * @catmap: the category bitmap
315  *
316  * Description:
317  * Free a LSM secattr catmap.
318  *
319  */
320 static inline void netlbl_catmap_free(struct netlbl_lsm_catmap *catmap)
321 {
322 	struct netlbl_lsm_catmap *iter;
323 
324 	while (catmap) {
325 		iter = catmap;
326 		catmap = catmap->next;
327 		kfree(iter);
328 	}
329 }
330 
331 /**
332  * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
333  * @secattr: the struct to initialize
334  *
335  * Description:
336  * Initialize an already allocated netlbl_lsm_secattr struct.
337  *
338  */
339 static inline void netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
340 {
341 	memset(secattr, 0, sizeof(*secattr));
342 }
343 
344 /**
345  * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
346  * @secattr: the struct to clear
347  *
348  * Description:
349  * Destroys the @secattr struct, including freeing all of the internal buffers.
350  * The struct must be reset with a call to netlbl_secattr_init() before reuse.
351  *
352  */
353 static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr)
354 {
355 	if (secattr->flags & NETLBL_SECATTR_FREE_DOMAIN)
356 		kfree(secattr->domain);
357 	if (secattr->flags & NETLBL_SECATTR_CACHE)
358 		netlbl_secattr_cache_free(secattr->cache);
359 	if (secattr->flags & NETLBL_SECATTR_MLS_CAT)
360 		netlbl_catmap_free(secattr->attr.mls.cat);
361 }
362 
363 /**
364  * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
365  * @flags: the memory allocation flags
366  *
367  * Description:
368  * Allocate and initialize a netlbl_lsm_secattr struct.  Returns a valid
369  * pointer on success, or NULL on failure.
370  *
371  */
372 static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(gfp_t flags)
373 {
374 	return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
375 }
376 
377 /**
378  * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
379  * @secattr: the struct to free
380  *
381  * Description:
382  * Frees @secattr including all of the internal buffers.
383  *
384  */
385 static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr)
386 {
387 	netlbl_secattr_destroy(secattr);
388 	kfree(secattr);
389 }
390 
391 #ifdef CONFIG_NETLABEL
392 /*
393  * LSM configuration operations
394  */
395 int netlbl_cfg_map_del(const char *domain,
396 		       u16 family,
397 		       const void *addr,
398 		       const void *mask,
399 		       struct netlbl_audit *audit_info);
400 int netlbl_cfg_unlbl_map_add(const char *domain,
401 			     u16 family,
402 			     const void *addr,
403 			     const void *mask,
404 			     struct netlbl_audit *audit_info);
405 int netlbl_cfg_unlbl_static_add(struct net *net,
406 				const char *dev_name,
407 				const void *addr,
408 				const void *mask,
409 				u16 family,
410 				u32 secid,
411 				struct netlbl_audit *audit_info);
412 int netlbl_cfg_unlbl_static_del(struct net *net,
413 				const char *dev_name,
414 				const void *addr,
415 				const void *mask,
416 				u16 family,
417 				struct netlbl_audit *audit_info);
418 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
419 			   struct netlbl_audit *audit_info);
420 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info);
421 int netlbl_cfg_cipsov4_map_add(u32 doi,
422 			       const char *domain,
423 			       const struct in_addr *addr,
424 			       const struct in_addr *mask,
425 			       struct netlbl_audit *audit_info);
426 /*
427  * LSM security attribute operations
428  */
429 int netlbl_catmap_walk(struct netlbl_lsm_catmap *catmap, u32 offset);
430 int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap, u32 offset);
431 int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap,
432 			  u32 *offset,
433 			  unsigned long *bitmap);
434 int netlbl_catmap_setbit(struct netlbl_lsm_catmap **catmap,
435 			 u32 bit,
436 			 gfp_t flags);
437 int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap,
438 			 u32 start,
439 			 u32 end,
440 			 gfp_t flags);
441 int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,
442 			  u32 offset,
443 			  unsigned long bitmap,
444 			  gfp_t flags);
445 
446 /* Bitmap functions
447  */
448 int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len,
449 		       u32 offset, u8 state);
450 void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state);
451 
452 /*
453  * LSM protocol operations (NetLabel LSM/kernel API)
454  */
455 int netlbl_enabled(void);
456 int netlbl_sock_setattr(struct sock *sk,
457 			u16 family,
458 			const struct netlbl_lsm_secattr *secattr);
459 void netlbl_sock_delattr(struct sock *sk);
460 int netlbl_sock_getattr(struct sock *sk,
461 			struct netlbl_lsm_secattr *secattr);
462 int netlbl_conn_setattr(struct sock *sk,
463 			struct sockaddr *addr,
464 			const struct netlbl_lsm_secattr *secattr);
465 int netlbl_req_setattr(struct request_sock *req,
466 		       const struct netlbl_lsm_secattr *secattr);
467 void netlbl_req_delattr(struct request_sock *req);
468 int netlbl_skbuff_setattr(struct sk_buff *skb,
469 			  u16 family,
470 			  const struct netlbl_lsm_secattr *secattr);
471 int netlbl_skbuff_getattr(const struct sk_buff *skb,
472 			  u16 family,
473 			  struct netlbl_lsm_secattr *secattr);
474 void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway);
475 
476 /*
477  * LSM label mapping cache operations
478  */
479 void netlbl_cache_invalidate(void);
480 int netlbl_cache_add(const struct sk_buff *skb,
481 		     const struct netlbl_lsm_secattr *secattr);
482 
483 /*
484  * Protocol engine operations
485  */
486 struct audit_buffer *netlbl_audit_start(int type,
487 					struct netlbl_audit *audit_info);
488 #else
489 static inline int netlbl_cfg_map_del(const char *domain,
490 				     u16 family,
491 				     const void *addr,
492 				     const void *mask,
493 				     struct netlbl_audit *audit_info)
494 {
495 	return -ENOSYS;
496 }
497 static inline int netlbl_cfg_unlbl_map_add(const char *domain,
498 					   u16 family,
499 					   void *addr,
500 					   void *mask,
501 					   struct netlbl_audit *audit_info)
502 {
503 	return -ENOSYS;
504 }
505 static inline int netlbl_cfg_unlbl_static_add(struct net *net,
506 					      const char *dev_name,
507 					      const void *addr,
508 					      const void *mask,
509 					      u16 family,
510 					      u32 secid,
511 					      struct netlbl_audit *audit_info)
512 {
513 	return -ENOSYS;
514 }
515 static inline int netlbl_cfg_unlbl_static_del(struct net *net,
516 					      const char *dev_name,
517 					      const void *addr,
518 					      const void *mask,
519 					      u16 family,
520 					      struct netlbl_audit *audit_info)
521 {
522 	return -ENOSYS;
523 }
524 static inline int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
525 					 struct netlbl_audit *audit_info)
526 {
527 	return -ENOSYS;
528 }
529 static inline void netlbl_cfg_cipsov4_del(u32 doi,
530 					  struct netlbl_audit *audit_info)
531 {
532 	return;
533 }
534 static inline int netlbl_cfg_cipsov4_map_add(u32 doi,
535 					     const char *domain,
536 					     const struct in_addr *addr,
537 					     const struct in_addr *mask,
538 					     struct netlbl_audit *audit_info)
539 {
540 	return -ENOSYS;
541 }
542 static inline int netlbl_catmap_walk(struct netlbl_lsm_catmap *catmap,
543 				     u32 offset)
544 {
545 	return -ENOENT;
546 }
547 static inline int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap,
548 					u32 offset)
549 {
550 	return -ENOENT;
551 }
552 static inline int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap,
553 					u32 *offset,
554 					unsigned long *bitmap)
555 {
556 	return 0;
557 }
558 static inline int netlbl_catmap_setbit(struct netlbl_lsm_catmap **catmap,
559 				       u32 bit,
560 				       gfp_t flags)
561 {
562 	return 0;
563 }
564 static inline int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap,
565 				       u32 start,
566 				       u32 end,
567 				       gfp_t flags)
568 {
569 	return 0;
570 }
571 static inline int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,
572 					u32 offset,
573 					unsigned long bitmap,
574 					gfp_t flags)
575 {
576 	return 0;
577 }
578 static inline int netlbl_enabled(void)
579 {
580 	return 0;
581 }
582 static inline int netlbl_sock_setattr(struct sock *sk,
583 				      u16 family,
584 				      const struct netlbl_lsm_secattr *secattr)
585 {
586 	return -ENOSYS;
587 }
588 static inline void netlbl_sock_delattr(struct sock *sk)
589 {
590 }
591 static inline int netlbl_sock_getattr(struct sock *sk,
592 				      struct netlbl_lsm_secattr *secattr)
593 {
594 	return -ENOSYS;
595 }
596 static inline int netlbl_conn_setattr(struct sock *sk,
597 				      struct sockaddr *addr,
598 				      const struct netlbl_lsm_secattr *secattr)
599 {
600 	return -ENOSYS;
601 }
602 static inline int netlbl_req_setattr(struct request_sock *req,
603 				     const struct netlbl_lsm_secattr *secattr)
604 {
605 	return -ENOSYS;
606 }
607 static inline void netlbl_req_delattr(struct request_sock *req)
608 {
609 	return;
610 }
611 static inline int netlbl_skbuff_setattr(struct sk_buff *skb,
612 				      u16 family,
613 				      const struct netlbl_lsm_secattr *secattr)
614 {
615 	return -ENOSYS;
616 }
617 static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
618 					u16 family,
619 					struct netlbl_lsm_secattr *secattr)
620 {
621 	return -ENOSYS;
622 }
623 static inline void netlbl_skbuff_err(struct sk_buff *skb,
624 				     int error,
625 				     int gateway)
626 {
627 	return;
628 }
629 static inline void netlbl_cache_invalidate(void)
630 {
631 	return;
632 }
633 static inline int netlbl_cache_add(const struct sk_buff *skb,
634 				   const struct netlbl_lsm_secattr *secattr)
635 {
636 	return 0;
637 }
638 static inline struct audit_buffer *netlbl_audit_start(int type,
639 						struct netlbl_audit *audit_info)
640 {
641 	return NULL;
642 }
643 #endif /* CONFIG_NETLABEL */
644 
645 const struct netlbl_calipso_ops *
646 netlbl_calipso_ops_register(const struct netlbl_calipso_ops *ops);
647 
648 #endif /* _NETLABEL_H */
649