xref: /openbmc/linux/include/net/cipso_ipv4.h (revision de528723) 
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * CIPSO - Commercial IP Security Option
4  *
5  * This is an implementation of the CIPSO 2.2 protocol as specified in
6  * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
7  * FIPS-188, copies of both documents can be found in the Documentation
8  * directory.  While CIPSO never became a full IETF RFC standard many vendors
9  * have chosen to adopt the protocol and over the years it has become a
10  * de-facto standard for labeled networking.
11  *
12  * Author: Paul Moore <paul@paul-moore.com>
13  */
14 
15 /*
16  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
17  */
18 
19 #ifndef _CIPSO_IPV4_H
20 #define _CIPSO_IPV4_H
21 
22 #include <linux/types.h>
23 #include <linux/rcupdate.h>
24 #include <linux/list.h>
25 #include <linux/net.h>
26 #include <linux/skbuff.h>
27 #include <net/netlabel.h>
28 #include <net/request_sock.h>
29 #include <linux/atomic.h>
30 #include <linux/refcount.h>
31 #include <asm/unaligned.h>
32 
33 /* known doi values */
34 #define CIPSO_V4_DOI_UNKNOWN          0x00000000
35 
36 /* standard tag types */
37 #define CIPSO_V4_TAG_INVALID          0
38 #define CIPSO_V4_TAG_RBITMAP          1
39 #define CIPSO_V4_TAG_ENUM             2
40 #define CIPSO_V4_TAG_RANGE            5
41 #define CIPSO_V4_TAG_PBITMAP          6
42 #define CIPSO_V4_TAG_FREEFORM         7
43 
44 /* non-standard tag types (tags > 127) */
45 #define CIPSO_V4_TAG_LOCAL            128
46 
47 /* doi mapping types */
48 #define CIPSO_V4_MAP_UNKNOWN          0
49 #define CIPSO_V4_MAP_TRANS            1
50 #define CIPSO_V4_MAP_PASS             2
51 #define CIPSO_V4_MAP_LOCAL            3
52 
53 /* limits */
54 #define CIPSO_V4_MAX_REM_LVLS         255
55 #define CIPSO_V4_INV_LVL              0x80000000
56 #define CIPSO_V4_MAX_LOC_LVLS         (CIPSO_V4_INV_LVL - 1)
57 #define CIPSO_V4_MAX_REM_CATS         65534
58 #define CIPSO_V4_INV_CAT              0x80000000
59 #define CIPSO_V4_MAX_LOC_CATS         (CIPSO_V4_INV_CAT - 1)
60 
61 /*
62  * CIPSO DOI definitions
63  */
64 
65 /* DOI definition struct */
66 #define CIPSO_V4_TAG_MAXCNT           5
67 struct cipso_v4_doi {
68 	u32 doi;
69 	u32 type;
70 	union {
71 		struct cipso_v4_std_map_tbl *std;
72 	} map;
73 	u8 tags[CIPSO_V4_TAG_MAXCNT];
74 
75 	refcount_t refcount;
76 	struct list_head list;
77 	struct rcu_head rcu;
78 };
79 
80 /* Standard CIPSO mapping table */
81 /* NOTE: the highest order bit (i.e. 0x80000000) is an 'invalid' flag, if the
82  *       bit is set then consider that value as unspecified, meaning the
83  *       mapping for that particular level/category is invalid */
84 struct cipso_v4_std_map_tbl {
85 	struct {
86 		u32 *cipso;
87 		u32 *local;
88 		u32 cipso_size;
89 		u32 local_size;
90 	} lvl;
91 	struct {
92 		u32 *cipso;
93 		u32 *local;
94 		u32 cipso_size;
95 		u32 local_size;
96 	} cat;
97 };
98 
99 /*
100  * Sysctl Variables
101  */
102 
103 #ifdef CONFIG_NETLABEL
104 extern int cipso_v4_cache_enabled;
105 extern int cipso_v4_cache_bucketsize;
106 extern int cipso_v4_rbm_optfmt;
107 extern int cipso_v4_rbm_strictvalid;
108 #endif
109 
110 /*
111  * DOI List Functions
112  */
113 
114 #ifdef CONFIG_NETLABEL
115 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
116 		     struct netlbl_audit *audit_info);
117 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
118 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
119 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
120 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
121 int cipso_v4_doi_walk(u32 *skip_cnt,
122 		     int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
123 	             void *cb_arg);
124 #else
125 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
126 				   struct netlbl_audit *audit_info)
127 {
128 	return -ENOSYS;
129 }
130 
131 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
132 {
133 	return;
134 }
135 
136 static inline int cipso_v4_doi_remove(u32 doi,
137 				      struct netlbl_audit *audit_info)
138 {
139 	return 0;
140 }
141 
142 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
143 {
144 	return NULL;
145 }
146 
147 static inline int cipso_v4_doi_walk(u32 *skip_cnt,
148 		     int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
149 		     void *cb_arg)
150 {
151 	return 0;
152 }
153 
154 static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def,
155 					  const char *domain)
156 {
157 	return -ENOSYS;
158 }
159 
160 static inline int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
161 					     const char *domain)
162 {
163 	return 0;
164 }
165 #endif /* CONFIG_NETLABEL */
166 
167 /*
168  * Label Mapping Cache Functions
169  */
170 
171 #ifdef CONFIG_NETLABEL
172 void cipso_v4_cache_invalidate(void);
173 int cipso_v4_cache_add(const unsigned char *cipso_ptr,
174 		       const struct netlbl_lsm_secattr *secattr);
175 #else
176 static inline void cipso_v4_cache_invalidate(void)
177 {
178 	return;
179 }
180 
181 static inline int cipso_v4_cache_add(const unsigned char *cipso_ptr,
182 				     const struct netlbl_lsm_secattr *secattr)
183 {
184 	return 0;
185 }
186 #endif /* CONFIG_NETLABEL */
187 
188 /*
189  * Protocol Handling Functions
190  */
191 
192 #ifdef CONFIG_NETLABEL
193 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
194 int cipso_v4_getattr(const unsigned char *cipso,
195 		     struct netlbl_lsm_secattr *secattr);
196 int cipso_v4_sock_setattr(struct sock *sk,
197 			  const struct cipso_v4_doi *doi_def,
198 			  const struct netlbl_lsm_secattr *secattr);
199 void cipso_v4_sock_delattr(struct sock *sk);
200 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
201 int cipso_v4_req_setattr(struct request_sock *req,
202 			 const struct cipso_v4_doi *doi_def,
203 			 const struct netlbl_lsm_secattr *secattr);
204 void cipso_v4_req_delattr(struct request_sock *req);
205 int cipso_v4_skbuff_setattr(struct sk_buff *skb,
206 			    const struct cipso_v4_doi *doi_def,
207 			    const struct netlbl_lsm_secattr *secattr);
208 int cipso_v4_skbuff_delattr(struct sk_buff *skb);
209 int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
210 			    struct netlbl_lsm_secattr *secattr);
211 unsigned char *cipso_v4_optptr(const struct sk_buff *skb);
212 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
213 #else
214 static inline void cipso_v4_error(struct sk_buff *skb,
215 				  int error,
216 				  u32 gateway)
217 {
218 	return;
219 }
220 
221 static inline int cipso_v4_getattr(const unsigned char *cipso,
222 				   struct netlbl_lsm_secattr *secattr)
223 {
224 	return -ENOSYS;
225 }
226 
227 static inline int cipso_v4_sock_setattr(struct sock *sk,
228 				      const struct cipso_v4_doi *doi_def,
229 				      const struct netlbl_lsm_secattr *secattr)
230 {
231 	return -ENOSYS;
232 }
233 
234 static inline void cipso_v4_sock_delattr(struct sock *sk)
235 {
236 }
237 
238 static inline int cipso_v4_sock_getattr(struct sock *sk,
239 					struct netlbl_lsm_secattr *secattr)
240 {
241 	return -ENOSYS;
242 }
243 
244 static inline int cipso_v4_req_setattr(struct request_sock *req,
245 				       const struct cipso_v4_doi *doi_def,
246 				       const struct netlbl_lsm_secattr *secattr)
247 {
248 	return -ENOSYS;
249 }
250 
251 static inline void cipso_v4_req_delattr(struct request_sock *req)
252 {
253 	return;
254 }
255 
256 static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
257 				      const struct cipso_v4_doi *doi_def,
258 				      const struct netlbl_lsm_secattr *secattr)
259 {
260 	return -ENOSYS;
261 }
262 
263 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
264 {
265 	return -ENOSYS;
266 }
267 
268 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
269 					  struct netlbl_lsm_secattr *secattr)
270 {
271 	return -ENOSYS;
272 }
273 
274 static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
275 {
276 	return NULL;
277 }
278 
279 static inline int cipso_v4_validate(const struct sk_buff *skb,
280 				    unsigned char **option)
281 {
282 	unsigned char *opt = *option;
283 	unsigned char err_offset = 0;
284 	u8 opt_len = opt[1];
285 	u8 opt_iter;
286 	u8 tag_len;
287 
288 	if (opt_len < 8) {
289 		err_offset = 1;
290 		goto out;
291 	}
292 
293 	if (get_unaligned_be32(&opt[2]) == 0) {
294 		err_offset = 2;
295 		goto out;
296 	}
297 
298 	for (opt_iter = 6; opt_iter < opt_len;) {
299 		if (opt_iter + 1 == opt_len) {
300 			err_offset = opt_iter;
301 			goto out;
302 		}
303 		tag_len = opt[opt_iter + 1];
304 		if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
305 			err_offset = opt_iter + 1;
306 			goto out;
307 		}
308 		opt_iter += tag_len;
309 	}
310 
311 out:
312 	*option = opt + err_offset;
313 	return err_offset;
314 
315 }
316 #endif /* CONFIG_NETLABEL */
317 
318 #endif /* _CIPSO_IPV4_H */
319