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 <linux/refcount.h>
45#include <asm/unaligned.h>
46
47/* known doi values */
48#define CIPSO_V4_DOI_UNKNOWN 0x00000000
49
50/* standard tag types */
51#define CIPSO_V4_TAG_INVALID 0
52#define CIPSO_V4_TAG_RBITMAP 1
53#define CIPSO_V4_TAG_ENUM 2
54#define CIPSO_V4_TAG_RANGE 5
55#define CIPSO_V4_TAG_PBITMAP 6
56#define CIPSO_V4_TAG_FREEFORM 7
57
58/* non-standard tag types (tags > 127) */
59#define CIPSO_V4_TAG_LOCAL 128
60
61/* doi mapping types */
62#define CIPSO_V4_MAP_UNKNOWN 0
63#define CIPSO_V4_MAP_TRANS 1
64#define CIPSO_V4_MAP_PASS 2
65#define CIPSO_V4_MAP_LOCAL 3
66
67/* limits */
68#define CIPSO_V4_MAX_REM_LVLS 255
69#define CIPSO_V4_INV_LVL 0x80000000
70#define CIPSO_V4_MAX_LOC_LVLS (CIPSO_V4_INV_LVL - 1)
71#define CIPSO_V4_MAX_REM_CATS 65534
72#define CIPSO_V4_INV_CAT 0x80000000
73#define CIPSO_V4_MAX_LOC_CATS (CIPSO_V4_INV_CAT - 1)
74
75/*
76 * CIPSO DOI definitions
77 */
78
79/* DOI definition struct */
80#define CIPSO_V4_TAG_MAXCNT 5
81struct cipso_v4_doi {
82 u32 doi;
83 u32 type;
84 union {
85 struct cipso_v4_std_map_tbl *std;
86 } map;
87 u8 tags[CIPSO_V4_TAG_MAXCNT];
88
89 refcount_t refcount;
90 struct list_head list;
91 struct rcu_head rcu;
92};
93
94/* Standard CIPSO mapping table */
95/* NOTE: the highest order bit (i.e. 0x80000000) is an 'invalid' flag, if the
96 * bit is set then consider that value as unspecified, meaning the
97 * mapping for that particular level/category is invalid */
98struct cipso_v4_std_map_tbl {
99 struct {
100 u32 *cipso;
101 u32 *local;
102 u32 cipso_size;
103 u32 local_size;
104 } lvl;
105 struct {
106 u32 *cipso;
107 u32 *local;
108 u32 cipso_size;
109 u32 local_size;
110 } cat;
111};
112
113/*
114 * Sysctl Variables
115 */
116
117#ifdef CONFIG_NETLABEL
118extern int cipso_v4_cache_enabled;
119extern int cipso_v4_cache_bucketsize;
120extern int cipso_v4_rbm_optfmt;
121extern int cipso_v4_rbm_strictvalid;
122#endif
123
124/*
125 * DOI List Functions
126 */
127
128#ifdef CONFIG_NETLABEL
129int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
130 struct netlbl_audit *audit_info);
131void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
132int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
133struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
134void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
135int cipso_v4_doi_walk(u32 *skip_cnt,
136 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
137 void *cb_arg);
138#else
139static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
140 struct netlbl_audit *audit_info)
141{
142 return -ENOSYS;
143}
144
145static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
146{
147 return;
148}
149
150static inline int cipso_v4_doi_remove(u32 doi,
151 struct netlbl_audit *audit_info)
152{
153 return 0;
154}
155
156static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
157{
158 return NULL;
159}
160
161static inline int cipso_v4_doi_walk(u32 *skip_cnt,
162 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
163 void *cb_arg)
164{
165 return 0;
166}
167
168static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def,
169 const char *domain)
170{
171 return -ENOSYS;
172}
173
174static inline int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
175 const char *domain)
176{
177 return 0;
178}
179#endif /* CONFIG_NETLABEL */
180
181/*
182 * Label Mapping Cache Functions
183 */
184
185#ifdef CONFIG_NETLABEL
186void cipso_v4_cache_invalidate(void);
187int cipso_v4_cache_add(const unsigned char *cipso_ptr,
188 const struct netlbl_lsm_secattr *secattr);
189#else
190static inline void cipso_v4_cache_invalidate(void)
191{
192 return;
193}
194
195static inline int cipso_v4_cache_add(const unsigned char *cipso_ptr,
196 const struct netlbl_lsm_secattr *secattr)
197{
198 return 0;
199}
200#endif /* CONFIG_NETLABEL */
201
202/*
203 * Protocol Handling Functions
204 */
205
206#ifdef CONFIG_NETLABEL
207void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
208int cipso_v4_getattr(const unsigned char *cipso,
209 struct netlbl_lsm_secattr *secattr);
210int cipso_v4_sock_setattr(struct sock *sk,
211 const struct cipso_v4_doi *doi_def,
212 const struct netlbl_lsm_secattr *secattr);
213void cipso_v4_sock_delattr(struct sock *sk);
214int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
215int cipso_v4_req_setattr(struct request_sock *req,
216 const struct cipso_v4_doi *doi_def,
217 const struct netlbl_lsm_secattr *secattr);
218void cipso_v4_req_delattr(struct request_sock *req);
219int cipso_v4_skbuff_setattr(struct sk_buff *skb,
220 const struct cipso_v4_doi *doi_def,
221 const struct netlbl_lsm_secattr *secattr);
222int cipso_v4_skbuff_delattr(struct sk_buff *skb);
223int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
224 struct netlbl_lsm_secattr *secattr);
225unsigned char *cipso_v4_optptr(const struct sk_buff *skb);
226int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
227#else
228static inline void cipso_v4_error(struct sk_buff *skb,
229 int error,
230 u32 gateway)
231{
232 return;
233}
234
235static inline int cipso_v4_getattr(const unsigned char *cipso,
236 struct netlbl_lsm_secattr *secattr)
237{
238 return -ENOSYS;
239}
240
241static inline int cipso_v4_sock_setattr(struct sock *sk,
242 const struct cipso_v4_doi *doi_def,
243 const struct netlbl_lsm_secattr *secattr)
244{
245 return -ENOSYS;
246}
247
248static inline void cipso_v4_sock_delattr(struct sock *sk)
249{
250}
251
252static inline int cipso_v4_sock_getattr(struct sock *sk,
253 struct netlbl_lsm_secattr *secattr)
254{
255 return -ENOSYS;
256}
257
258static inline int cipso_v4_req_setattr(struct request_sock *req,
259 const struct cipso_v4_doi *doi_def,
260 const struct netlbl_lsm_secattr *secattr)
261{
262 return -ENOSYS;
263}
264
265static inline void cipso_v4_req_delattr(struct request_sock *req)
266{
267 return;
268}
269
270static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
271 const struct cipso_v4_doi *doi_def,
272 const struct netlbl_lsm_secattr *secattr)
273{
274 return -ENOSYS;
275}
276
277static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
278{
279 return -ENOSYS;
280}
281
282static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
283 struct netlbl_lsm_secattr *secattr)
284{
285 return -ENOSYS;
286}
287
288static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
289{
290 return NULL;
291}
292
293static inline int cipso_v4_validate(const struct sk_buff *skb,
294 unsigned char **option)
295{
296 unsigned char *opt = *option;
297 unsigned char err_offset = 0;
298 u8 opt_len = opt[1];
299 u8 opt_iter;
300 u8 tag_len;
301
302 if (opt_len < 8) {
303 err_offset = 1;
304 goto out;
305 }
306
307 if (get_unaligned_be32(&opt[2]) == 0) {
308 err_offset = 2;
309 goto out;
310 }
311
312 for (opt_iter = 6; opt_iter < opt_len;) {
313 if (opt_iter + 1 == opt_len) {
314 err_offset = opt_iter;
315 goto out;
316 }
317 tag_len = opt[opt_iter + 1];
318 if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
319 err_offset = opt_iter + 1;
320 goto out;
321 }
322 opt_iter += tag_len;
323 }
324
325out:
326 *option = opt + err_offset;
327 return err_offset;
328
329}
330#endif /* CONFIG_NETLABEL */
331
332#endif /* _CIPSO_IPV4_H */
333