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 81 struct 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 */ 98 struct 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 118 extern int cipso_v4_cache_enabled; 119 extern int cipso_v4_cache_bucketsize; 120 extern int cipso_v4_rbm_optfmt; 121 extern int cipso_v4_rbm_strictvalid; 122 #endif 123 124 /* 125 * DOI List Functions 126 */ 127 128 #ifdef CONFIG_NETLABEL 129 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, 130 struct netlbl_audit *audit_info); 131 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def); 132 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info); 133 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi); 134 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def); 135 int cipso_v4_doi_walk(u32 *skip_cnt, 136 int (*callback) (struct cipso_v4_doi *doi_def, void *arg), 137 void *cb_arg); 138 #else 139 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, 140 struct netlbl_audit *audit_info) 141 { 142 return -ENOSYS; 143 } 144 145 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) 146 { 147 return; 148 } 149 150 static inline int cipso_v4_doi_remove(u32 doi, 151 struct netlbl_audit *audit_info) 152 { 153 return 0; 154 } 155 156 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) 157 { 158 return NULL; 159 } 160 161 static 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 } 167 168 static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, 169 const char *domain) 170 { 171 return -ENOSYS; 172 } 173 174 static 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 186 void cipso_v4_cache_invalidate(void); 187 int cipso_v4_cache_add(const unsigned char *cipso_ptr, 188 const struct netlbl_lsm_secattr *secattr); 189 #else 190 static inline void cipso_v4_cache_invalidate(void) 191 { 192 return; 193 } 194 195 static 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 207 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway); 208 int cipso_v4_getattr(const unsigned char *cipso, 209 struct netlbl_lsm_secattr *secattr); 210 int cipso_v4_sock_setattr(struct sock *sk, 211 const struct cipso_v4_doi *doi_def, 212 const struct netlbl_lsm_secattr *secattr); 213 void cipso_v4_sock_delattr(struct sock *sk); 214 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr); 215 int cipso_v4_req_setattr(struct request_sock *req, 216 const struct cipso_v4_doi *doi_def, 217 const struct netlbl_lsm_secattr *secattr); 218 void cipso_v4_req_delattr(struct request_sock *req); 219 int cipso_v4_skbuff_setattr(struct sk_buff *skb, 220 const struct cipso_v4_doi *doi_def, 221 const struct netlbl_lsm_secattr *secattr); 222 int cipso_v4_skbuff_delattr(struct sk_buff *skb); 223 int cipso_v4_skbuff_getattr(const struct sk_buff *skb, 224 struct netlbl_lsm_secattr *secattr); 225 unsigned char *cipso_v4_optptr(const struct sk_buff *skb); 226 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option); 227 #else 228 static inline void cipso_v4_error(struct sk_buff *skb, 229 int error, 230 u32 gateway) 231 { 232 return; 233 } 234 235 static inline int cipso_v4_getattr(const unsigned char *cipso, 236 struct netlbl_lsm_secattr *secattr) 237 { 238 return -ENOSYS; 239 } 240 241 static 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 } 247 248 static inline void cipso_v4_sock_delattr(struct sock *sk) 249 { 250 } 251 252 static inline int cipso_v4_sock_getattr(struct sock *sk, 253 struct netlbl_lsm_secattr *secattr) 254 { 255 return -ENOSYS; 256 } 257 258 static 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 } 264 265 static inline void cipso_v4_req_delattr(struct request_sock *req) 266 { 267 return; 268 } 269 270 static 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 } 276 277 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb) 278 { 279 return -ENOSYS; 280 } 281 282 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb, 283 struct netlbl_lsm_secattr *secattr) 284 { 285 return -ENOSYS; 286 } 287 288 static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb) 289 { 290 return NULL; 291 } 292 293 static 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 } 324 325 out: 326 *option = opt + err_offset; 327 return err_offset; 328 329 } 330 #endif /* CONFIG_NETLABEL */ 331 332 #endif /* _CIPSO_IPV4_H */ 333