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 <linux/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
67struct 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 */
84struct 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
104extern int cipso_v4_cache_enabled;
105extern int cipso_v4_cache_bucketsize;
106extern int cipso_v4_rbm_optfmt;
107extern int cipso_v4_rbm_strictvalid;
108#endif
109
110/*
111 * DOI List Functions
112 */
113
114#ifdef CONFIG_NETLABEL
115int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
116 struct netlbl_audit *audit_info);
117void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
118int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
119struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
120void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
121int cipso_v4_doi_walk(u32 *skip_cnt,
122 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
123 void *cb_arg);
124#else
125static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
126 struct netlbl_audit *audit_info)
127{
128 return -ENOSYS;
129}
130
131static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
132{
133 return;
134}
135
136static inline int cipso_v4_doi_remove(u32 doi,
137 struct netlbl_audit *audit_info)
138{
139 return 0;
140}
141
142static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
143{
144 return NULL;
145}
146
147static 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#endif /* CONFIG_NETLABEL */
154
155/*
156 * Label Mapping Cache Functions
157 */
158
159#ifdef CONFIG_NETLABEL
160void cipso_v4_cache_invalidate(void);
161int cipso_v4_cache_add(const unsigned char *cipso_ptr,
162 const struct netlbl_lsm_secattr *secattr);
163#else
164static inline void cipso_v4_cache_invalidate(void)
165{
166 return;
167}
168
169static inline int cipso_v4_cache_add(const unsigned char *cipso_ptr,
170 const struct netlbl_lsm_secattr *secattr)
171{
172 return 0;
173}
174#endif /* CONFIG_NETLABEL */
175
176/*
177 * Protocol Handling Functions
178 */
179
180#ifdef CONFIG_NETLABEL
181void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
182int cipso_v4_getattr(const unsigned char *cipso,
183 struct netlbl_lsm_secattr *secattr);
184int cipso_v4_sock_setattr(struct sock *sk,
185 const struct cipso_v4_doi *doi_def,
186 const struct netlbl_lsm_secattr *secattr,
187 bool sk_locked);
188void cipso_v4_sock_delattr(struct sock *sk);
189int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
190int cipso_v4_req_setattr(struct request_sock *req,
191 const struct cipso_v4_doi *doi_def,
192 const struct netlbl_lsm_secattr *secattr);
193void cipso_v4_req_delattr(struct request_sock *req);
194int cipso_v4_skbuff_setattr(struct sk_buff *skb,
195 const struct cipso_v4_doi *doi_def,
196 const struct netlbl_lsm_secattr *secattr);
197int cipso_v4_skbuff_delattr(struct sk_buff *skb);
198int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
199 struct netlbl_lsm_secattr *secattr);
200unsigned char *cipso_v4_optptr(const struct sk_buff *skb);
201int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
202#else
203static inline void cipso_v4_error(struct sk_buff *skb,
204 int error,
205 u32 gateway)
206{
207 return;
208}
209
210static inline int cipso_v4_getattr(const unsigned char *cipso,
211 struct netlbl_lsm_secattr *secattr)
212{
213 return -ENOSYS;
214}
215
216static inline int cipso_v4_sock_setattr(struct sock *sk,
217 const struct cipso_v4_doi *doi_def,
218 const struct netlbl_lsm_secattr *secattr,
219 bool sk_locked)
220{
221 return -ENOSYS;
222}
223
224static inline void cipso_v4_sock_delattr(struct sock *sk)
225{
226}
227
228static inline int cipso_v4_sock_getattr(struct sock *sk,
229 struct netlbl_lsm_secattr *secattr)
230{
231 return -ENOSYS;
232}
233
234static inline int cipso_v4_req_setattr(struct request_sock *req,
235 const struct cipso_v4_doi *doi_def,
236 const struct netlbl_lsm_secattr *secattr)
237{
238 return -ENOSYS;
239}
240
241static inline void cipso_v4_req_delattr(struct request_sock *req)
242{
243 return;
244}
245
246static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
247 const struct cipso_v4_doi *doi_def,
248 const struct netlbl_lsm_secattr *secattr)
249{
250 return -ENOSYS;
251}
252
253static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
254{
255 return -ENOSYS;
256}
257
258static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
259 struct netlbl_lsm_secattr *secattr)
260{
261 return -ENOSYS;
262}
263
264static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
265{
266 return NULL;
267}
268
269static inline int cipso_v4_validate(const struct sk_buff *skb,
270 unsigned char **option)
271{
272 unsigned char *opt = *option;
273 unsigned char err_offset = 0;
274 u8 opt_len = opt[1];
275 u8 opt_iter;
276 u8 tag_len;
277
278 if (opt_len < 8) {
279 err_offset = 1;
280 goto out;
281 }
282
283 if (get_unaligned_be32(&opt[2]) == 0) {
284 err_offset = 2;
285 goto out;
286 }
287
288 for (opt_iter = 6; opt_iter < opt_len;) {
289 if (opt_iter + 1 == opt_len) {
290 err_offset = opt_iter;
291 goto out;
292 }
293 tag_len = opt[opt_iter + 1];
294 if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
295 err_offset = opt_iter + 1;
296 goto out;
297 }
298 opt_iter += tag_len;
299 }
300
301out:
302 *option = opt + err_offset;
303 return err_offset;
304
305}
306#endif /* CONFIG_NETLABEL */
307
308#endif /* _CIPSO_IPV4_H */
309