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, write to the Free Software 30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 31 * 32 */ 33 34 #ifndef _CIPSO_IPV4_H 35 #define _CIPSO_IPV4_H 36 37 #include <linux/types.h> 38 #include <linux/rcupdate.h> 39 #include <linux/list.h> 40 #include <linux/net.h> 41 #include <linux/skbuff.h> 42 #include <net/netlabel.h> 43 #include <net/request_sock.h> 44 #include <linux/atomic.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 atomic_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 * Helper Functions 126 */ 127 128 #define CIPSO_V4_OPTEXIST(x) (IPCB(x)->opt.cipso != 0) 129 #define CIPSO_V4_OPTPTR(x) (skb_network_header(x) + IPCB(x)->opt.cipso) 130 131 /* 132 * DOI List Functions 133 */ 134 135 #ifdef CONFIG_NETLABEL 136 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, 137 struct netlbl_audit *audit_info); 138 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def); 139 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info); 140 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi); 141 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def); 142 int cipso_v4_doi_walk(u32 *skip_cnt, 143 int (*callback) (struct cipso_v4_doi *doi_def, void *arg), 144 void *cb_arg); 145 #else 146 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, 147 struct netlbl_audit *audit_info) 148 { 149 return -ENOSYS; 150 } 151 152 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) 153 { 154 return; 155 } 156 157 static inline int cipso_v4_doi_remove(u32 doi, 158 struct netlbl_audit *audit_info) 159 { 160 return 0; 161 } 162 163 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) 164 { 165 return NULL; 166 } 167 168 static inline int cipso_v4_doi_walk(u32 *skip_cnt, 169 int (*callback) (struct cipso_v4_doi *doi_def, void *arg), 170 void *cb_arg) 171 { 172 return 0; 173 } 174 175 static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, 176 const char *domain) 177 { 178 return -ENOSYS; 179 } 180 181 static inline int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def, 182 const char *domain) 183 { 184 return 0; 185 } 186 #endif /* CONFIG_NETLABEL */ 187 188 /* 189 * Label Mapping Cache Functions 190 */ 191 192 #ifdef CONFIG_NETLABEL 193 void cipso_v4_cache_invalidate(void); 194 int cipso_v4_cache_add(const struct sk_buff *skb, 195 const struct netlbl_lsm_secattr *secattr); 196 #else 197 static inline void cipso_v4_cache_invalidate(void) 198 { 199 return; 200 } 201 202 static inline int cipso_v4_cache_add(const struct sk_buff *skb, 203 const struct netlbl_lsm_secattr *secattr) 204 { 205 return 0; 206 } 207 #endif /* CONFIG_NETLABEL */ 208 209 /* 210 * Protocol Handling Functions 211 */ 212 213 #ifdef CONFIG_NETLABEL 214 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway); 215 int cipso_v4_sock_setattr(struct sock *sk, 216 const struct cipso_v4_doi *doi_def, 217 const struct netlbl_lsm_secattr *secattr); 218 void cipso_v4_sock_delattr(struct sock *sk); 219 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr); 220 int cipso_v4_req_setattr(struct request_sock *req, 221 const struct cipso_v4_doi *doi_def, 222 const struct netlbl_lsm_secattr *secattr); 223 void cipso_v4_req_delattr(struct request_sock *req); 224 int cipso_v4_skbuff_setattr(struct sk_buff *skb, 225 const struct cipso_v4_doi *doi_def, 226 const struct netlbl_lsm_secattr *secattr); 227 int cipso_v4_skbuff_delattr(struct sk_buff *skb); 228 int cipso_v4_skbuff_getattr(const struct sk_buff *skb, 229 struct netlbl_lsm_secattr *secattr); 230 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option); 231 #else 232 static inline void cipso_v4_error(struct sk_buff *skb, 233 int error, 234 u32 gateway) 235 { 236 return; 237 } 238 239 static inline int cipso_v4_sock_setattr(struct sock *sk, 240 const struct cipso_v4_doi *doi_def, 241 const struct netlbl_lsm_secattr *secattr) 242 { 243 return -ENOSYS; 244 } 245 246 static inline void cipso_v4_sock_delattr(struct sock *sk) 247 { 248 } 249 250 static inline int cipso_v4_sock_getattr(struct sock *sk, 251 struct netlbl_lsm_secattr *secattr) 252 { 253 return -ENOSYS; 254 } 255 256 static inline int cipso_v4_req_setattr(struct request_sock *req, 257 const struct cipso_v4_doi *doi_def, 258 const struct netlbl_lsm_secattr *secattr) 259 { 260 return -ENOSYS; 261 } 262 263 static inline void cipso_v4_req_delattr(struct request_sock *req) 264 { 265 return; 266 } 267 268 static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb, 269 const struct cipso_v4_doi *doi_def, 270 const struct netlbl_lsm_secattr *secattr) 271 { 272 return -ENOSYS; 273 } 274 275 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb) 276 { 277 return -ENOSYS; 278 } 279 280 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb, 281 struct netlbl_lsm_secattr *secattr) 282 { 283 return -ENOSYS; 284 } 285 286 static inline int cipso_v4_validate(const struct sk_buff *skb, 287 unsigned char **option) 288 { 289 unsigned char *opt = *option; 290 unsigned char err_offset = 0; 291 u8 opt_len = opt[1]; 292 u8 opt_iter; 293 u8 tag_len; 294 295 if (opt_len < 8) { 296 err_offset = 1; 297 goto out; 298 } 299 300 if (get_unaligned_be32(&opt[2]) == 0) { 301 err_offset = 2; 302 goto out; 303 } 304 305 for (opt_iter = 6; opt_iter < opt_len;) { 306 tag_len = opt[opt_iter + 1]; 307 if ((tag_len == 0) || (opt[opt_iter + 1] > (opt_len - opt_iter))) { 308 err_offset = opt_iter + 1; 309 goto out; 310 } 311 opt_iter += tag_len; 312 } 313 314 out: 315 *option = opt + err_offset; 316 return err_offset; 317 318 } 319 #endif /* CONFIG_NETLABEL */ 320 321 #endif /* _CIPSO_IPV4_H */ 322