summaryrefslogtreecommitdiffstats
path: root/include/net/netlabel.h
blob: 5e53a85b5ca1bc56014a192b50304800298ae386 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
/*
 * NetLabel System
 *
 * The NetLabel system manages static and dynamic label mappings for network
 * protocols such as CIPSO and RIPSO.
 *
 * Author: Paul Moore <paul.moore@hp.com>
 *
 */

/*
 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY;  without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 * the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program;  if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#ifndef _NETLABEL_H
#define _NETLABEL_H

#include <linux/types.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <asm/atomic.h>

struct cipso_v4_doi;

/*
 * NetLabel - A management interface for maintaining network packet label
 *            mapping tables for explicit packet labling protocols.
 *
 * Network protocols such as CIPSO and RIPSO require a label translation layer
 * to convert the label on the packet into something meaningful on the host
 * machine.  In the current Linux implementation these mapping tables live
 * inside the kernel; NetLabel provides a mechanism for user space applications
 * to manage these mapping tables.
 *
 * NetLabel makes use of the Generic NETLINK mechanism as a transport layer to
 * send messages between kernel and user space.  The general format of a
 * NetLabel message is shown below:
 *
 *  +-----------------+-------------------+--------- --- -- -
 *  | struct nlmsghdr | struct genlmsghdr | payload
 *  +-----------------+-------------------+--------- --- -- -
 *
 * The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal.
 * The payload is dependent on the subsystem specified in the
 * 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions
 * should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c
 * file.  All of the fields in the NetLabel payload are NETLINK attributes, see
 * the include/net/netlink.h file for more information on NETLINK attributes.
 *
 */

/*
 * NetLabel NETLINK protocol
 */

/* NetLabel NETLINK protocol version
 *  1: initial version
 *  2: added static labels for unlabeled connections
 */
#define NETLBL_PROTO_VERSION            2

/* NetLabel NETLINK types/families */
#define NETLBL_NLTYPE_NONE              0
#define NETLBL_NLTYPE_MGMT              1
#define NETLBL_NLTYPE_MGMT_NAME         "NLBL_MGMT"
#define NETLBL_NLTYPE_RIPSO             2
#define NETLBL_NLTYPE_RIPSO_NAME        "NLBL_RIPSO"
#define NETLBL_NLTYPE_CIPSOV4           3
#define NETLBL_NLTYPE_CIPSOV4_NAME      "NLBL_CIPSOv4"
#define NETLBL_NLTYPE_CIPSOV6           4
#define NETLBL_NLTYPE_CIPSOV6_NAME      "NLBL_CIPSOv6"
#define NETLBL_NLTYPE_UNLABELED         5
#define NETLBL_NLTYPE_UNLABELED_NAME    "NLBL_UNLBL"

/*
 * NetLabel - Kernel API for accessing the network packet label mappings.
 *
 * The following functions are provided for use by other kernel modules,
 * specifically kernel LSM modules, to provide a consistent, transparent API
 * for dealing with explicit packet labeling protocols such as CIPSO and
 * RIPSO.  The functions defined here are implemented in the
 * net/netlabel/netlabel_kapi.c file.
 *
 */

/* NetLabel audit information */
struct netlbl_audit {
	u32 secid;
	uid_t loginuid;
};

/*
 * LSM security attributes
 */

/**
 * struct netlbl_lsm_cache - NetLabel LSM security attribute cache
 * @refcount: atomic reference counter
 * @free: LSM supplied function to free the cache data
 * @data: LSM supplied cache data
 *
 * Description:
 * This structure is provided for LSMs which wish to make use of the NetLabel
 * caching mechanism to store LSM specific data/attributes in the NetLabel
 * cache.  If the LSM has to perform a lot of translation from the NetLabel
 * security attributes into it's own internal representation then the cache
 * mechanism can provide a way to eliminate some or all of that translation
 * overhead on a cache hit.
 *
 */
struct netlbl_lsm_cache {
	atomic_t refcount;
	void (*free) (const void *data);
	void *data;
};

/**
 * struct netlbl_lsm_secattr_catmap - NetLabel LSM secattr category bitmap
 * @startbit: the value of the lowest order bit in the bitmap
 * @bitmap: the category bitmap
 * @next: pointer to the next bitmap "node" or NULL
 *
 * Description:
 * This structure is used to represent category bitmaps.  Due to the large
 * number of categories supported by most labeling protocols it is not
 * practical to transfer a full bitmap internally so NetLabel adopts a sparse
 * bitmap structure modeled after SELinux's ebitmap structure.
 * The catmap bitmap field MUST be a power of two in length and large
 * enough to hold at least 240 bits.  Special care (i.e. check the code!)
 * should be used when changing these values as the LSM implementation
 * probably has functions which rely on the sizes of these types to speed
 * processing.
 *
 */
#define NETLBL_CATMAP_MAPTYPE           u64
#define NETLBL_CATMAP_MAPCNT            4
#define NETLBL_CATMAP_MAPSIZE           (sizeof(NETLBL_CATMAP_MAPTYPE) * 8)
#define NETLBL_CATMAP_SIZE              (NETLBL_CATMAP_MAPSIZE * \
					 NETLBL_CATMAP_MAPCNT)
#define NETLBL_CATMAP_BIT               (NETLBL_CATMAP_MAPTYPE)0x01
struct netlbl_lsm_secattr_catmap {
	u32 startbit;
	NETLBL_CATMAP_MAPTYPE bitmap[NETLBL_CATMAP_MAPCNT];
	struct netlbl_lsm_secattr_catmap *next;
};

/**
 * struct netlbl_lsm_secattr - NetLabel LSM security attributes
 * @flags: indicate structure attributes, see NETLBL_SECATTR_*
 * @type: indicate the NLTYPE of the attributes
 * @domain: the NetLabel LSM domain
 * @cache: NetLabel LSM specific cache
 * @attr.mls: MLS sensitivity label
 * @attr.mls.cat: MLS category bitmap
 * @attr.mls.lvl: MLS sensitivity level
 * @attr.secid: LSM specific secid token
 *
 * Description:
 * This structure is used to pass security attributes between NetLabel and the
 * LSM modules.  The flags field is used to specify which fields within the
 * struct are valid and valid values can be created by bitwise OR'ing the
 * NETLBL_SECATTR_* defines.  The domain field is typically set by the LSM to
 * specify domain specific configuration settings and is not usually used by
 * NetLabel itself when returning security attributes to the LSM.
 *
 */
struct netlbl_lsm_secattr {
	u32 flags;
	/* bitmap values for 'flags' */
#define NETLBL_SECATTR_NONE             0x00000000
#define NETLBL_SECATTR_DOMAIN           0x00000001
#define NETLBL_SECATTR_DOMAIN_CPY       (NETLBL_SECATTR_DOMAIN | \
					 NETLBL_SECATTR_FREE_DOMAIN)
#define NETLBL_SECATTR_CACHE            0x00000002
#define NETLBL_SECATTR_MLS_LVL          0x00000004
#define NETLBL_SECATTR_MLS_CAT          0x00000008
#define NETLBL_SECATTR_SECID            0x00000010
	/* bitmap meta-values for 'flags' */
#define NETLBL_SECATTR_FREE_DOMAIN      0x01000000
#define NETLBL_SECATTR_CACHEABLE        (NETLBL_SECATTR_MLS_LVL | \
					 NETLBL_SECATTR_MLS_CAT | \
					 NETLBL_SECATTR_SECID)
	u32 type;
	char *domain;
	struct netlbl_lsm_cache *cache;
	union {
		struct {
			struct netlbl_lsm_secattr_catmap *cat;
			u32 lvl;
		} mls;
		u32 secid;
	} attr;
};

/*
 * LSM security attribute operations (inline)
 */

/**
 * netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache
 * @flags: the memory allocation flags
 *
 * Description:
 * Allocate and initialize a netlbl_lsm_cache structure.  Returns a pointer
 * on success, NULL on failure.
 *
 */
static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags)
{
	struct netlbl_lsm_cache *cache;

	cache = kzalloc(sizeof(*cache), flags);
	if (cache)
		atomic_set(&cache->refcount, 1);
	return cache;
}

/**
 * netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct
 * @cache: the struct to free
 *
 * Description:
 * Frees @secattr including all of the internal buffers.
 *
 */
static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache)
{
	if (!atomic_dec_and_test(&cache->refcount))
		return;

	if (cache->free)
		cache->free(cache->data);
	kfree(cache);
}

/**
 * netlbl_secattr_catmap_alloc - Allocate a LSM secattr catmap
 * @flags: memory allocation flags
 *
 * Description:
 * Allocate memory for a LSM secattr catmap, returns a pointer on success, NULL
 * on failure.
 *
 */
static inline struct netlbl_lsm_secattr_catmap *netlbl_secattr_catmap_alloc(
	                                                           gfp_t flags)
{
	return kzalloc(sizeof(struct netlbl_lsm_secattr_catmap), flags);
}

/**
 * netlbl_secattr_catmap_free - Free a LSM secattr catmap
 * @catmap: the category bitmap
 *
 * Description:
 * Free a LSM secattr catmap.
 *
 */
static inline void netlbl_secattr_catmap_free(
	                              struct netlbl_lsm_secattr_catmap *catmap)
{
	struct netlbl_lsm_secattr_catmap *iter;

	do {
		iter = catmap;
		catmap = catmap->next;
		kfree(iter);
	} while (catmap);
}

/**
 * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
 * @secattr: the struct to initialize
 *
 * Description:
 * Initialize an already allocated netlbl_lsm_secattr struct.
 *
 */
static inline void netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
{
	memset(secattr, 0, sizeof(*secattr));
}

/**
 * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
 * @secattr: the struct to clear
 *
 * Description:
 * Destroys the @secattr struct, including freeing all of the internal buffers.
 * The struct must be reset with a call to netlbl_secattr_init() before reuse.
 *
 */
static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr)
{
	if (secattr->flags & NETLBL_SECATTR_FREE_DOMAIN)
		kfree(secattr->domain);
	if (secattr->flags & NETLBL_SECATTR_CACHE)
		netlbl_secattr_cache_free(secattr->cache);
	if (secattr->flags & NETLBL_SECATTR_MLS_CAT)
		netlbl_secattr_catmap_free(secattr->attr.mls.cat);
}

/**
 * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
 * @flags: the memory allocation flags
 *
 * Description:
 * Allocate and initialize a netlbl_lsm_secattr struct.  Returns a valid
 * pointer on success, or NULL on failure.
 *
 */
static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(gfp_t flags)
{
	return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
}

/**
 * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
 * @secattr: the struct to free
 *
 * Description:
 * Frees @secattr including all of the internal buffers.
 *
 */
static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr)
{
	netlbl_secattr_destroy(secattr);
	kfree(secattr);
}

#ifdef CONFIG_NETLABEL
/*
 * LSM configuration operations
 */
int netlbl_cfg_map_del(const char *domain, struct netlbl_audit *audit_info);
int netlbl_cfg_unlbl_add_map(const char *domain,
			     struct netlbl_audit *audit_info);
int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
			   struct netlbl_audit *audit_info);
int netlbl_cfg_cipsov4_add_map(struct cipso_v4_doi *doi_def,
			       const char *domain,
			       struct netlbl_audit *audit_info);
int netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info);

/*
 * LSM security attribute operations
 */
int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
			       u32 offset);
int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
				   u32 offset);
int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
				 u32 bit,
				 gfp_t flags);
int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
				 u32 start,
				 u32 end,
				 gfp_t flags);

/*
 * LSM protocol operations (NetLabel LSM/kernel API)
 */
int netlbl_enabled(void);
int netlbl_sock_setattr(struct sock *sk,
			const struct netlbl_lsm_secattr *secattr);
int netlbl_sock_getattr(struct sock *sk,
			struct netlbl_lsm_secattr *secattr);
int netlbl_skbuff_getattr(const struct sk_buff *skb,
			  u16 family,
			  struct netlbl_lsm_secattr *secattr);
void netlbl_skbuff_err(struct sk_buff *skb, int error);

/*
 * LSM label mapping cache operations
 */
void netlbl_cache_invalidate(void);
int netlbl_cache_add(const struct sk_buff *skb,
		     const struct netlbl_lsm_secattr *secattr);
#else
static inline int netlbl_cfg_map_del(const char *domain,
				     struct netlbl_audit *audit_info)
{
	return -ENOSYS;
}
static inline int netlbl_cfg_unlbl_add_map(const char *domain,
					   struct netlbl_audit *audit_info)
{
	return -ENOSYS;
}
static inline int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
					 struct netlbl_audit *audit_info)
{
	return -ENOSYS;
}
static inline int netlbl_cfg_cipsov4_add_map(struct cipso_v4_doi *doi_def,
					     const char *domain,
					     struct netlbl_audit *audit_info)
{
	return -ENOSYS;
}
static inline int netlbl_cfg_cipsov4_del(u32 doi,
					 struct netlbl_audit *audit_info)
{
	return -ENOSYS;
}
static inline int netlbl_secattr_catmap_walk(
	                              struct netlbl_lsm_secattr_catmap *catmap,
				      u32 offset)
{
	return -ENOENT;
}
static inline int netlbl_secattr_catmap_walk_rng(
				      struct netlbl_lsm_secattr_catmap *catmap,
				      u32 offset)
{
	return -ENOENT;
}
static inline int netlbl_secattr_catmap_setbit(
	                              struct netlbl_lsm_secattr_catmap *catmap,
				      u32 bit,
				      gfp_t flags)
{
	return 0;
}
static inline int netlbl_secattr_catmap_setrng(
	                              struct netlbl_lsm_secattr_catmap *catmap,
				      u32 start,
				      u32 end,
				      gfp_t flags)
{
	return 0;
}
static inline int netlbl_enabled(void)
{
	return 0;
}
static inline int netlbl_sock_setattr(struct sock *sk,
				     const struct netlbl_lsm_secattr *secattr)
{
	return -ENOSYS;
}
static inline int netlbl_sock_getattr(struct sock *sk,
				      struct netlbl_lsm_secattr *secattr)
{
	return -ENOSYS;
}
static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
					u16 family,
					struct netlbl_lsm_secattr *secattr)
{
	return -ENOSYS;
}
static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
{
	return;
}
static inline void netlbl_cache_invalidate(void)
{
	return;
}
static inline int netlbl_cache_add(const struct sk_buff *skb,
				   const struct netlbl_lsm_secattr *secattr)
{
	return 0;
}
#endif /* CONFIG_NETLABEL */

#endif /* _NETLABEL_H */