1 /* 2 * NetLabel System 3 * 4 * The NetLabel system manages static and dynamic label mappings for network 5 * protocols such as CIPSO and RIPSO. 6 * 7 * Author: Paul Moore <paul.moore@hp.com> 8 * 9 */ 10 11 /* 12 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 22 * the GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, write to the Free Software 26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 27 * 28 */ 29 30 #ifndef _NETLABEL_H 31 #define _NETLABEL_H 32 33 #include <linux/types.h> 34 #include <linux/net.h> 35 #include <linux/skbuff.h> 36 #include <net/netlink.h> 37 #include <asm/atomic.h> 38 39 /* 40 * NetLabel - A management interface for maintaining network packet label 41 * mapping tables for explicit packet labling protocols. 42 * 43 * Network protocols such as CIPSO and RIPSO require a label translation layer 44 * to convert the label on the packet into something meaningful on the host 45 * machine. In the current Linux implementation these mapping tables live 46 * inside the kernel; NetLabel provides a mechanism for user space applications 47 * to manage these mapping tables. 48 * 49 * NetLabel makes use of the Generic NETLINK mechanism as a transport layer to 50 * send messages between kernel and user space. The general format of a 51 * NetLabel message is shown below: 52 * 53 * +-----------------+-------------------+--------- --- -- - 54 * | struct nlmsghdr | struct genlmsghdr | payload 55 * +-----------------+-------------------+--------- --- -- - 56 * 57 * The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal. 58 * The payload is dependent on the subsystem specified in the 59 * 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions 60 * should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c 61 * file. All of the fields in the NetLabel payload are NETLINK attributes, see 62 * the include/net/netlink.h file for more information on NETLINK attributes. 63 * 64 */ 65 66 /* 67 * NetLabel NETLINK protocol 68 */ 69 70 #define NETLBL_PROTO_VERSION 1 71 72 /* NetLabel NETLINK types/families */ 73 #define NETLBL_NLTYPE_NONE 0 74 #define NETLBL_NLTYPE_MGMT 1 75 #define NETLBL_NLTYPE_MGMT_NAME "NLBL_MGMT" 76 #define NETLBL_NLTYPE_RIPSO 2 77 #define NETLBL_NLTYPE_RIPSO_NAME "NLBL_RIPSO" 78 #define NETLBL_NLTYPE_CIPSOV4 3 79 #define NETLBL_NLTYPE_CIPSOV4_NAME "NLBL_CIPSOv4" 80 #define NETLBL_NLTYPE_CIPSOV6 4 81 #define NETLBL_NLTYPE_CIPSOV6_NAME "NLBL_CIPSOv6" 82 #define NETLBL_NLTYPE_UNLABELED 5 83 #define NETLBL_NLTYPE_UNLABELED_NAME "NLBL_UNLBL" 84 85 /* 86 * NetLabel - Kernel API for accessing the network packet label mappings. 87 * 88 * The following functions are provided for use by other kernel modules, 89 * specifically kernel LSM modules, to provide a consistent, transparent API 90 * for dealing with explicit packet labeling protocols such as CIPSO and 91 * RIPSO. The functions defined here are implemented in the 92 * net/netlabel/netlabel_kapi.c file. 93 * 94 */ 95 96 /* NetLabel audit information */ 97 struct netlbl_audit { 98 u32 secid; 99 uid_t loginuid; 100 }; 101 102 /* Domain mapping definition struct */ 103 struct netlbl_dom_map; 104 105 /* Domain mapping operations */ 106 int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info); 107 108 /* LSM security attributes */ 109 struct netlbl_lsm_cache { 110 atomic_t refcount; 111 void (*free) (const void *data); 112 void *data; 113 }; 114 /* The catmap bitmap field MUST be a power of two in length and large 115 * enough to hold at least 240 bits. Special care (i.e. check the code!) 116 * should be used when changing these values as the LSM implementation 117 * probably has functions which rely on the sizes of these types to speed 118 * processing. */ 119 #define NETLBL_CATMAP_MAPTYPE u64 120 #define NETLBL_CATMAP_MAPCNT 4 121 #define NETLBL_CATMAP_MAPSIZE (sizeof(NETLBL_CATMAP_MAPTYPE) * 8) 122 #define NETLBL_CATMAP_SIZE (NETLBL_CATMAP_MAPSIZE * \ 123 NETLBL_CATMAP_MAPCNT) 124 #define NETLBL_CATMAP_BIT (NETLBL_CATMAP_MAPTYPE)0x01 125 struct netlbl_lsm_secattr_catmap { 126 u32 startbit; 127 NETLBL_CATMAP_MAPTYPE bitmap[NETLBL_CATMAP_MAPCNT]; 128 struct netlbl_lsm_secattr_catmap *next; 129 }; 130 #define NETLBL_SECATTR_NONE 0x00000000 131 #define NETLBL_SECATTR_DOMAIN 0x00000001 132 #define NETLBL_SECATTR_CACHE 0x00000002 133 #define NETLBL_SECATTR_MLS_LVL 0x00000004 134 #define NETLBL_SECATTR_MLS_CAT 0x00000008 135 struct netlbl_lsm_secattr { 136 u32 flags; 137 138 char *domain; 139 140 u32 mls_lvl; 141 struct netlbl_lsm_secattr_catmap *mls_cat; 142 143 struct netlbl_lsm_cache *cache; 144 }; 145 146 /* 147 * LSM security attribute operations (inline) 148 */ 149 150 /** 151 * netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache 152 * @flags: the memory allocation flags 153 * 154 * Description: 155 * Allocate and initialize a netlbl_lsm_cache structure. Returns a pointer 156 * on success, NULL on failure. 157 * 158 */ 159 static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags) 160 { 161 struct netlbl_lsm_cache *cache; 162 163 cache = kzalloc(sizeof(*cache), flags); 164 if (cache) 165 atomic_set(&cache->refcount, 1); 166 return cache; 167 } 168 169 /** 170 * netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct 171 * @cache: the struct to free 172 * 173 * Description: 174 * Frees @secattr including all of the internal buffers. 175 * 176 */ 177 static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache) 178 { 179 if (!atomic_dec_and_test(&cache->refcount)) 180 return; 181 182 if (cache->free) 183 cache->free(cache->data); 184 kfree(cache); 185 } 186 187 /** 188 * netlbl_secattr_catmap_alloc - Allocate a LSM secattr catmap 189 * @flags: memory allocation flags 190 * 191 * Description: 192 * Allocate memory for a LSM secattr catmap, returns a pointer on success, NULL 193 * on failure. 194 * 195 */ 196 static inline struct netlbl_lsm_secattr_catmap *netlbl_secattr_catmap_alloc( 197 gfp_t flags) 198 { 199 return kzalloc(sizeof(struct netlbl_lsm_secattr_catmap), flags); 200 } 201 202 /** 203 * netlbl_secattr_catmap_free - Free a LSM secattr catmap 204 * @catmap: the category bitmap 205 * 206 * Description: 207 * Free a LSM secattr catmap. 208 * 209 */ 210 static inline void netlbl_secattr_catmap_free( 211 struct netlbl_lsm_secattr_catmap *catmap) 212 { 213 struct netlbl_lsm_secattr_catmap *iter; 214 215 do { 216 iter = catmap; 217 catmap = catmap->next; 218 kfree(iter); 219 } while (catmap); 220 } 221 222 /** 223 * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct 224 * @secattr: the struct to initialize 225 * 226 * Description: 227 * Initialize an already allocated netlbl_lsm_secattr struct. 228 * 229 */ 230 static inline void netlbl_secattr_init(struct netlbl_lsm_secattr *secattr) 231 { 232 secattr->flags = 0; 233 secattr->domain = NULL; 234 secattr->mls_cat = NULL; 235 secattr->cache = NULL; 236 } 237 238 /** 239 * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct 240 * @secattr: the struct to clear 241 * 242 * Description: 243 * Destroys the @secattr struct, including freeing all of the internal buffers. 244 * The struct must be reset with a call to netlbl_secattr_init() before reuse. 245 * 246 */ 247 static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr) 248 { 249 if (secattr->cache) 250 netlbl_secattr_cache_free(secattr->cache); 251 kfree(secattr->domain); 252 if (secattr->mls_cat) 253 netlbl_secattr_catmap_free(secattr->mls_cat); 254 } 255 256 /** 257 * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct 258 * @flags: the memory allocation flags 259 * 260 * Description: 261 * Allocate and initialize a netlbl_lsm_secattr struct. Returns a valid 262 * pointer on success, or NULL on failure. 263 * 264 */ 265 static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(gfp_t flags) 266 { 267 return kzalloc(sizeof(struct netlbl_lsm_secattr), flags); 268 } 269 270 /** 271 * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct 272 * @secattr: the struct to free 273 * 274 * Description: 275 * Frees @secattr including all of the internal buffers. 276 * 277 */ 278 static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr) 279 { 280 netlbl_secattr_destroy(secattr); 281 kfree(secattr); 282 } 283 284 #ifdef CONFIG_NETLABEL 285 /* 286 * LSM security attribute operations 287 */ 288 int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap, 289 u32 offset); 290 int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap, 291 u32 offset); 292 int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap, 293 u32 bit, 294 gfp_t flags); 295 int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap, 296 u32 start, 297 u32 end, 298 gfp_t flags); 299 300 /* 301 * LSM protocol operations 302 */ 303 int netlbl_enabled(void); 304 int netlbl_sock_setattr(struct sock *sk, 305 const struct netlbl_lsm_secattr *secattr); 306 int netlbl_sock_getattr(struct sock *sk, 307 struct netlbl_lsm_secattr *secattr); 308 int netlbl_skbuff_getattr(const struct sk_buff *skb, 309 struct netlbl_lsm_secattr *secattr); 310 void netlbl_skbuff_err(struct sk_buff *skb, int error); 311 312 /* 313 * LSM label mapping cache operations 314 */ 315 void netlbl_cache_invalidate(void); 316 int netlbl_cache_add(const struct sk_buff *skb, 317 const struct netlbl_lsm_secattr *secattr); 318 #else 319 static inline int netlbl_secattr_catmap_walk( 320 struct netlbl_lsm_secattr_catmap *catmap, 321 u32 offset) 322 { 323 return -ENOENT; 324 } 325 static inline int netlbl_secattr_catmap_walk_rng( 326 struct netlbl_lsm_secattr_catmap *catmap, 327 u32 offset) 328 { 329 return -ENOENT; 330 } 331 static inline int netlbl_secattr_catmap_setbit( 332 struct netlbl_lsm_secattr_catmap *catmap, 333 u32 bit, 334 gfp_t flags) 335 { 336 return 0; 337 } 338 static inline int netlbl_secattr_catmap_setrng( 339 struct netlbl_lsm_secattr_catmap *catmap, 340 u32 start, 341 u32 end, 342 gfp_t flags) 343 { 344 return 0; 345 } 346 static inline int netlbl_enabled(void) 347 { 348 return 0; 349 } 350 static inline int netlbl_sock_setattr(struct sock *sk, 351 const struct netlbl_lsm_secattr *secattr) 352 { 353 return -ENOSYS; 354 } 355 static inline int netlbl_sock_getattr(struct sock *sk, 356 struct netlbl_lsm_secattr *secattr) 357 { 358 return -ENOSYS; 359 } 360 static inline int netlbl_skbuff_getattr(const struct sk_buff *skb, 361 struct netlbl_lsm_secattr *secattr) 362 { 363 return -ENOSYS; 364 } 365 static inline void netlbl_skbuff_err(struct sk_buff *skb, int error) 366 { 367 return; 368 } 369 static inline void netlbl_cache_invalidate(void) 370 { 371 return; 372 } 373 static inline int netlbl_cache_add(const struct sk_buff *skb, 374 const struct netlbl_lsm_secattr *secattr) 375 { 376 return 0; 377 } 378 #endif /* CONFIG_NETLABEL */ 379 380 #endif /* _NETLABEL_H */ 381