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, 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 */