xref: /linux/include/net/cipso_ipv4.h (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * CIPSO - Commercial IP Security Option
3  *
4  * This is an implementation of the CIPSO 2.2 protocol as specified in
5  * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
6  * FIPS-188, copies of both documents can be found in the Documentation
7  * directory.  While CIPSO never became a full IETF RFC standard many vendors
8  * have chosen to adopt the protocol and over the years it has become a
9  * de-facto standard for labeled networking.
10  *
11  * Author: Paul Moore <paul@paul-moore.com>
12  *
13  */
14 
15 /*
16  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
17  *
18  * This program is free software;  you can redistribute it and/or modify
19  * it under the terms of the GNU General Public License as published by
20  * the Free Software Foundation; either version 2 of the License, or
21  * (at your option) any later version.
22  *
23  * This program is distributed in the hope that it will be useful,
24  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
26  * the GNU General Public License for more details.
27  *
28  * You should have received a copy of the GNU General Public License
29  * along with this program;  if not, see <http://www.gnu.org/licenses/>.
30  *
31  */
32 
33 #ifndef _CIPSO_IPV4_H
34 #define _CIPSO_IPV4_H
35 
36 #include <linux/types.h>
37 #include <linux/rcupdate.h>
38 #include <linux/list.h>
39 #include <linux/net.h>
40 #include <linux/skbuff.h>
41 #include <net/netlabel.h>
42 #include <net/request_sock.h>
43 #include <linux/atomic.h>
44 #include <asm/unaligned.h>
45 
46 /* known doi values */
47 #define CIPSO_V4_DOI_UNKNOWN          0x00000000
48 
49 /* standard tag types */
50 #define CIPSO_V4_TAG_INVALID          0
51 #define CIPSO_V4_TAG_RBITMAP          1
52 #define CIPSO_V4_TAG_ENUM             2
53 #define CIPSO_V4_TAG_RANGE            5
54 #define CIPSO_V4_TAG_PBITMAP          6
55 #define CIPSO_V4_TAG_FREEFORM         7
56 
57 /* non-standard tag types (tags > 127) */
58 #define CIPSO_V4_TAG_LOCAL            128
59 
60 /* doi mapping types */
61 #define CIPSO_V4_MAP_UNKNOWN          0
62 #define CIPSO_V4_MAP_TRANS            1
63 #define CIPSO_V4_MAP_PASS             2
64 #define CIPSO_V4_MAP_LOCAL            3
65 
66 /* limits */
67 #define CIPSO_V4_MAX_REM_LVLS         255
68 #define CIPSO_V4_INV_LVL              0x80000000
69 #define CIPSO_V4_MAX_LOC_LVLS         (CIPSO_V4_INV_LVL - 1)
70 #define CIPSO_V4_MAX_REM_CATS         65534
71 #define CIPSO_V4_INV_CAT              0x80000000
72 #define CIPSO_V4_MAX_LOC_CATS         (CIPSO_V4_INV_CAT - 1)
73 
74 /*
75  * CIPSO DOI definitions
76  */
77 
78 /* DOI definition struct */
79 #define CIPSO_V4_TAG_MAXCNT           5
80 struct cipso_v4_doi {
81 	u32 doi;
82 	u32 type;
83 	union {
84 		struct cipso_v4_std_map_tbl *std;
85 	} map;
86 	u8 tags[CIPSO_V4_TAG_MAXCNT];
87 
88 	atomic_t refcount;
89 	struct list_head list;
90 	struct rcu_head rcu;
91 };
92 
93 /* Standard CIPSO mapping table */
94 /* NOTE: the highest order bit (i.e. 0x80000000) is an 'invalid' flag, if the
95  *       bit is set then consider that value as unspecified, meaning the
96  *       mapping for that particular level/category is invalid */
97 struct cipso_v4_std_map_tbl {
98 	struct {
99 		u32 *cipso;
100 		u32 *local;
101 		u32 cipso_size;
102 		u32 local_size;
103 	} lvl;
104 	struct {
105 		u32 *cipso;
106 		u32 *local;
107 		u32 cipso_size;
108 		u32 local_size;
109 	} cat;
110 };
111 
112 /*
113  * Sysctl Variables
114  */
115 
116 #ifdef CONFIG_NETLABEL
117 extern int cipso_v4_cache_enabled;
118 extern int cipso_v4_cache_bucketsize;
119 extern int cipso_v4_rbm_optfmt;
120 extern int cipso_v4_rbm_strictvalid;
121 #endif
122 
123 /*
124  * DOI List Functions
125  */
126 
127 #ifdef CONFIG_NETLABEL
128 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
129 		     struct netlbl_audit *audit_info);
130 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
131 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
132 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
133 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
134 int cipso_v4_doi_walk(u32 *skip_cnt,
135 		     int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
136 	             void *cb_arg);
137 #else
138 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
139 				   struct netlbl_audit *audit_info)
140 {
141 	return -ENOSYS;
142 }
143 
144 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
145 {
146 	return;
147 }
148 
149 static inline int cipso_v4_doi_remove(u32 doi,
150 				      struct netlbl_audit *audit_info)
151 {
152 	return 0;
153 }
154 
155 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
156 {
157 	return NULL;
158 }
159 
160 static inline int cipso_v4_doi_walk(u32 *skip_cnt,
161 		     int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
162 		     void *cb_arg)
163 {
164 	return 0;
165 }
166 
167 static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def,
168 					  const char *domain)
169 {
170 	return -ENOSYS;
171 }
172 
173 static inline int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
174 					     const char *domain)
175 {
176 	return 0;
177 }
178 #endif /* CONFIG_NETLABEL */
179 
180 /*
181  * Label Mapping Cache Functions
182  */
183 
184 #ifdef CONFIG_NETLABEL
185 void cipso_v4_cache_invalidate(void);
186 int cipso_v4_cache_add(const unsigned char *cipso_ptr,
187 		       const struct netlbl_lsm_secattr *secattr);
188 #else
189 static inline void cipso_v4_cache_invalidate(void)
190 {
191 	return;
192 }
193 
194 static inline int cipso_v4_cache_add(const unsigned char *cipso_ptr,
195 				     const struct netlbl_lsm_secattr *secattr)
196 {
197 	return 0;
198 }
199 #endif /* CONFIG_NETLABEL */
200 
201 /*
202  * Protocol Handling Functions
203  */
204 
205 #ifdef CONFIG_NETLABEL
206 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
207 int cipso_v4_getattr(const unsigned char *cipso,
208 		     struct netlbl_lsm_secattr *secattr);
209 int cipso_v4_sock_setattr(struct sock *sk,
210 			  const struct cipso_v4_doi *doi_def,
211 			  const struct netlbl_lsm_secattr *secattr);
212 void cipso_v4_sock_delattr(struct sock *sk);
213 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
214 int cipso_v4_req_setattr(struct request_sock *req,
215 			 const struct cipso_v4_doi *doi_def,
216 			 const struct netlbl_lsm_secattr *secattr);
217 void cipso_v4_req_delattr(struct request_sock *req);
218 int cipso_v4_skbuff_setattr(struct sk_buff *skb,
219 			    const struct cipso_v4_doi *doi_def,
220 			    const struct netlbl_lsm_secattr *secattr);
221 int cipso_v4_skbuff_delattr(struct sk_buff *skb);
222 int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
223 			    struct netlbl_lsm_secattr *secattr);
224 unsigned char *cipso_v4_optptr(const struct sk_buff *skb);
225 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
226 #else
227 static inline void cipso_v4_error(struct sk_buff *skb,
228 				  int error,
229 				  u32 gateway)
230 {
231 	return;
232 }
233 
234 static inline int cipso_v4_getattr(const unsigned char *cipso,
235 				   struct netlbl_lsm_secattr *secattr)
236 {
237 	return -ENOSYS;
238 }
239 
240 static inline int cipso_v4_sock_setattr(struct sock *sk,
241 				      const struct cipso_v4_doi *doi_def,
242 				      const struct netlbl_lsm_secattr *secattr)
243 {
244 	return -ENOSYS;
245 }
246 
247 static inline void cipso_v4_sock_delattr(struct sock *sk)
248 {
249 }
250 
251 static inline int cipso_v4_sock_getattr(struct sock *sk,
252 					struct netlbl_lsm_secattr *secattr)
253 {
254 	return -ENOSYS;
255 }
256 
257 static inline int cipso_v4_req_setattr(struct request_sock *req,
258 				       const struct cipso_v4_doi *doi_def,
259 				       const struct netlbl_lsm_secattr *secattr)
260 {
261 	return -ENOSYS;
262 }
263 
264 static inline void cipso_v4_req_delattr(struct request_sock *req)
265 {
266 	return;
267 }
268 
269 static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
270 				      const struct cipso_v4_doi *doi_def,
271 				      const struct netlbl_lsm_secattr *secattr)
272 {
273 	return -ENOSYS;
274 }
275 
276 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
277 {
278 	return -ENOSYS;
279 }
280 
281 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
282 					  struct netlbl_lsm_secattr *secattr)
283 {
284 	return -ENOSYS;
285 }
286 
287 static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
288 {
289 	return NULL;
290 }
291 
292 static inline int cipso_v4_validate(const struct sk_buff *skb,
293 				    unsigned char **option)
294 {
295 	unsigned char *opt = *option;
296 	unsigned char err_offset = 0;
297 	u8 opt_len = opt[1];
298 	u8 opt_iter;
299 	u8 tag_len;
300 
301 	if (opt_len < 8) {
302 		err_offset = 1;
303 		goto out;
304 	}
305 
306 	if (get_unaligned_be32(&opt[2]) == 0) {
307 		err_offset = 2;
308 		goto out;
309 	}
310 
311 	for (opt_iter = 6; opt_iter < opt_len;) {
312 		if (opt_iter + 1 == opt_len) {
313 			err_offset = opt_iter;
314 			goto out;
315 		}
316 		tag_len = opt[opt_iter + 1];
317 		if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
318 			err_offset = opt_iter + 1;
319 			goto out;
320 		}
321 		opt_iter += tag_len;
322 	}
323 
324 out:
325 	*option = opt + err_offset;
326 	return err_offset;
327 
328 }
329 #endif /* CONFIG_NETLABEL */
330 
331 #endif /* _CIPSO_IPV4_H */
332