include/net/cipso_ipv4.h

   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 <asm/unaligned.h>
  45
  46 /* known doi values */
  47 #define CIPSO_V4_DOI_UNKNOWN          0x00000000
  48
  49 /* standard tag types */
  50 #define CIPSO_V4_TAG_INVALID          0
  51 #define CIPSO_V4_TAG_RBITMAP          1
  52 #define CIPSO_V4_TAG_ENUM             2
  53 #define CIPSO_V4_TAG_RANGE            5
  54 #define CIPSO_V4_TAG_PBITMAP          6
  55 #define CIPSO_V4_TAG_FREEFORM         7
  56
  57 /* non-standard tag types (tags > 127) */
  58 #define CIPSO_V4_TAG_LOCAL            128
  59
  60 /* doi mapping types */
  61 #define CIPSO_V4_MAP_UNKNOWN          0
  62 #define CIPSO_V4_MAP_TRANS            1
  63 #define CIPSO_V4_MAP_PASS             2
  64 #define CIPSO_V4_MAP_LOCAL            3
  65
  66 /* limits */
  67 #define CIPSO_V4_MAX_REM_LVLS         255
  68 #define CIPSO_V4_INV_LVL              0x80000000
  69 #define CIPSO_V4_MAX_LOC_LVLS         (CIPSO_V4_INV_LVL - 1)
  70 #define CIPSO_V4_MAX_REM_CATS         65534
  71 #define CIPSO_V4_INV_CAT              0x80000000
  72 #define CIPSO_V4_MAX_LOC_CATS         (CIPSO_V4_INV_CAT - 1)
  73
  74 /*
  75  * CIPSO DOI definitions
  76  */
  77
  78 /* DOI definition struct */
  79 #define CIPSO_V4_TAG_MAXCNT           5
  80 struct cipso_v4_doi {
  81         u32 doi;
  82         u32 type;
  83         union {
  84                 struct cipso_v4_std_map_tbl *std;
  85         } map;
  86         u8 tags[CIPSO_V4_TAG_MAXCNT];
  87
  88         atomic_t refcount;
  89         struct list_head list;
  90         struct rcu_head rcu;
  91 };
  92
  93 /* Standard CIPSO mapping table */
  94 /* NOTE: the highest order bit (i.e. 0x80000000) is an 'invalid' flag, if the
  95  *       bit is set then consider that value as unspecified, meaning the
  96  *       mapping for that particular level/category is invalid */
  97 struct cipso_v4_std_map_tbl {
  98         struct {
  99                 u32 *cipso;
 100                 u32 *local;
 101                 u32 cipso_size;
 102                 u32 local_size;
 103         } lvl;
 104         struct {
 105                 u32 *cipso;
 106                 u32 *local;
 107                 u32 cipso_size;
 108                 u32 local_size;
 109         } cat;
 110 };
 111
 112 /*
 113  * Sysctl Variables
 114  */
 115
 116 #ifdef CONFIG_NETLABEL
 117 extern int cipso_v4_cache_enabled;
 118 extern int cipso_v4_cache_bucketsize;
 119 extern int cipso_v4_rbm_optfmt;
 120 extern int cipso_v4_rbm_strictvalid;
 121 #endif
 122
 123 /*
 124  * Helper Functions
 125  */
 126
 127 #define CIPSO_V4_OPTEXIST(x) (IPCB(x)->opt.cipso != 0)
 128 #define CIPSO_V4_OPTPTR(x) (skb_network_header(x) + IPCB(x)->opt.cipso)
 129
 130 /*
 131  * DOI List Functions
 132  */
 133
 134 #ifdef CONFIG_NETLABEL
 135 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
 136                      struct netlbl_audit *audit_info);
 137 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
 138 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
 139 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
 140 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
 141 int cipso_v4_doi_walk(u32 *skip_cnt,
 142                      int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
 143                      void *cb_arg);
 144 #else
 145 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
 146                                    struct netlbl_audit *audit_info)
 147 {
 148         return -ENOSYS;
 149 }
 150
 151 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
 152 {
 153         return;
 154 }
 155
 156 static inline int cipso_v4_doi_remove(u32 doi,
 157                                       struct netlbl_audit *audit_info)
 158 {
 159         return 0;
 160 }
 161
 162 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
 163 {
 164         return NULL;
 165 }
 166
 167 static inline int cipso_v4_doi_walk(u32 *skip_cnt,
 168                      int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
 169                      void *cb_arg)
 170 {
 171         return 0;
 172 }
 173
 174 static inline int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def,
 175                                           const char *domain)
 176 {
 177         return -ENOSYS;
 178 }
 179
 180 static inline int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
 181                                              const char *domain)
 182 {
 183         return 0;
 184 }
 185 #endif /* CONFIG_NETLABEL */
 186
 187 /*
 188  * Label Mapping Cache Functions
 189  */
 190
 191 #ifdef CONFIG_NETLABEL
 192 void cipso_v4_cache_invalidate(void);
 193 int cipso_v4_cache_add(const struct sk_buff *skb,
 194                        const struct netlbl_lsm_secattr *secattr);
 195 #else
 196 static inline void cipso_v4_cache_invalidate(void)
 197 {
 198         return;
 199 }
 200
 201 static inline int cipso_v4_cache_add(const struct sk_buff *skb,
 202                                      const struct netlbl_lsm_secattr *secattr)
 203 {
 204         return 0;
 205 }
 206 #endif /* CONFIG_NETLABEL */
 207
 208 /*
 209  * Protocol Handling Functions
 210  */
 211
 212 #ifdef CONFIG_NETLABEL
 213 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
 214 int cipso_v4_sock_setattr(struct sock *sk,
 215                           const struct cipso_v4_doi *doi_def,
 216                           const struct netlbl_lsm_secattr *secattr);
 217 void cipso_v4_sock_delattr(struct sock *sk);
 218 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
 219 int cipso_v4_req_setattr(struct request_sock *req,
 220                          const struct cipso_v4_doi *doi_def,
 221                          const struct netlbl_lsm_secattr *secattr);
 222 void cipso_v4_req_delattr(struct request_sock *req);
 223 int cipso_v4_skbuff_setattr(struct sk_buff *skb,
 224                             const struct cipso_v4_doi *doi_def,
 225                             const struct netlbl_lsm_secattr *secattr);
 226 int cipso_v4_skbuff_delattr(struct sk_buff *skb);
 227 int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
 228                             struct netlbl_lsm_secattr *secattr);
 229 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
 230 #else
 231 static inline void cipso_v4_error(struct sk_buff *skb,
 232                                   int error,
 233                                   u32 gateway)
 234 {
 235         return;
 236 }
 237
 238 static inline int cipso_v4_sock_setattr(struct sock *sk,
 239                                       const struct cipso_v4_doi *doi_def,
 240                                       const struct netlbl_lsm_secattr *secattr)
 241 {
 242         return -ENOSYS;
 243 }
 244
 245 static inline void cipso_v4_sock_delattr(struct sock *sk)
 246 {
 247 }
 248
 249 static inline int cipso_v4_sock_getattr(struct sock *sk,
 250                                         struct netlbl_lsm_secattr *secattr)
 251 {
 252         return -ENOSYS;
 253 }
 254
 255 static inline int cipso_v4_req_setattr(struct request_sock *req,
 256                                        const struct cipso_v4_doi *doi_def,
 257                                        const struct netlbl_lsm_secattr *secattr)
 258 {
 259         return -ENOSYS;
 260 }
 261
 262 static inline void cipso_v4_req_delattr(struct request_sock *req)
 263 {
 264         return;
 265 }
 266
 267 static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
 268                                       const struct cipso_v4_doi *doi_def,
 269                                       const struct netlbl_lsm_secattr *secattr)
 270 {
 271         return -ENOSYS;
 272 }
 273
 274 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
 275 {
 276         return -ENOSYS;
 277 }
 278
 279 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
 280                                           struct netlbl_lsm_secattr *secattr)
 281 {
 282         return -ENOSYS;
 283 }
 284
 285 static inline int cipso_v4_validate(const struct sk_buff *skb,
 286                                     unsigned char **option)
 287 {
 288         unsigned char *opt = *option;
 289         unsigned char err_offset = 0;
 290         u8 opt_len = opt[1];
 291         u8 opt_iter;
 292         u8 tag_len;
 293
 294         if (opt_len < 8) {
 295                 err_offset = 1;
 296                 goto out;
 297         }
 298
 299         if (get_unaligned_be32(&opt[2]) == 0) {
 300                 err_offset = 2;
 301                 goto out;
 302         }
 303
 304         for (opt_iter = 6; opt_iter < opt_len;) {
 305                 tag_len = opt[opt_iter + 1];
 306                 if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
 307                         err_offset = opt_iter + 1;
 308                         goto out;
 309                 }
 310                 opt_iter += tag_len;
 311         }
 312
 313 out:
 314         *option = opt + err_offset;
 315         return err_offset;
 316
 317 }
 318 #endif /* CONFIG_NETLABEL */
 319
 320 #endif /* _CIPSO_IPV4_H */