include/net/cipso_ipv4.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * CIPSO - Commercial IP Security Option
   4  *
   5  * This is an implementation of the CIPSO 2.2 protocol as specified in
   6  * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
   7  * FIPS-188, copies of both documents can be found in the Documentation
   8  * directory.  While CIPSO never became a full IETF RFC standard many vendors
   9  * have chosen to adopt the protocol and over the years it has become a
  10  * de-facto standard for labeled networking.
  11  *
  12  * Author: Paul Moore <paul@paul-moore.com>
  13  */
  14
  15 /*
  16  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
  17  */
  18
  19 #ifndef _CIPSO_IPV4_H
  20 #define _CIPSO_IPV4_H
  21
  22 #include <linux/types.h>
  23 #include <linux/rcupdate.h>
  24 #include <linux/list.h>
  25 #include <linux/net.h>
  26 #include <linux/skbuff.h>
  27 #include <net/netlabel.h>
  28 #include <net/request_sock.h>
  29 #include <linux/atomic.h>
  30 #include <linux/refcount.h>
  31 #include <linux/unaligned.h>
  32
  33 /* known doi values */
  34 #define CIPSO_V4_DOI_UNKNOWN          0x00000000
  35
  36 /* standard tag types */
  37 #define CIPSO_V4_TAG_INVALID          0
  38 #define CIPSO_V4_TAG_RBITMAP          1
  39 #define CIPSO_V4_TAG_ENUM             2
  40 #define CIPSO_V4_TAG_RANGE            5
  41 #define CIPSO_V4_TAG_PBITMAP          6
  42 #define CIPSO_V4_TAG_FREEFORM         7
  43
  44 /* non-standard tag types (tags > 127) */
  45 #define CIPSO_V4_TAG_LOCAL            128
  46
  47 /* doi mapping types */
  48 #define CIPSO_V4_MAP_UNKNOWN          0
  49 #define CIPSO_V4_MAP_TRANS            1
  50 #define CIPSO_V4_MAP_PASS             2
  51 #define CIPSO_V4_MAP_LOCAL            3
  52
  53 /* limits */
  54 #define CIPSO_V4_MAX_REM_LVLS         255
  55 #define CIPSO_V4_INV_LVL              0x80000000
  56 #define CIPSO_V4_MAX_LOC_LVLS         (CIPSO_V4_INV_LVL - 1)
  57 #define CIPSO_V4_MAX_REM_CATS         65534
  58 #define CIPSO_V4_INV_CAT              0x80000000
  59 #define CIPSO_V4_MAX_LOC_CATS         (CIPSO_V4_INV_CAT - 1)
  60
  61 /*
  62  * CIPSO DOI definitions
  63  */
  64
  65 /* DOI definition struct */
  66 #define CIPSO_V4_TAG_MAXCNT           5
  67 struct cipso_v4_doi {
  68         u32 doi;
  69         u32 type;
  70         union {
  71                 struct cipso_v4_std_map_tbl *std;
  72         } map;
  73         u8 tags[CIPSO_V4_TAG_MAXCNT];
  74
  75         refcount_t refcount;
  76         struct list_head list;
  77         struct rcu_head rcu;
  78 };
  79
  80 /* Standard CIPSO mapping table */
  81 /* NOTE: the highest order bit (i.e. 0x80000000) is an 'invalid' flag, if the
  82  *       bit is set then consider that value as unspecified, meaning the
  83  *       mapping for that particular level/category is invalid */
  84 struct cipso_v4_std_map_tbl {
  85         struct {
  86                 u32 *cipso;
  87                 u32 *local;
  88                 u32 cipso_size;
  89                 u32 local_size;
  90         } lvl;
  91         struct {
  92                 u32 *cipso;
  93                 u32 *local;
  94                 u32 cipso_size;
  95                 u32 local_size;
  96         } cat;
  97 };
  98
  99 /*
 100  * Sysctl Variables
 101  */
 102
 103 #ifdef CONFIG_NETLABEL
 104 extern int cipso_v4_cache_enabled;
 105 extern int cipso_v4_cache_bucketsize;
 106 extern int cipso_v4_rbm_optfmt;
 107 extern int cipso_v4_rbm_strictvalid;
 108 #endif
 109
 110 /*
 111  * DOI List Functions
 112  */
 113
 114 #ifdef CONFIG_NETLABEL
 115 int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
 116                      struct netlbl_audit *audit_info);
 117 void cipso_v4_doi_free(struct cipso_v4_doi *doi_def);
 118 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info);
 119 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi);
 120 void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def);
 121 int cipso_v4_doi_walk(u32 *skip_cnt,
 122                      int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
 123                      void *cb_arg);
 124 #else
 125 static inline int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
 126                                    struct netlbl_audit *audit_info)
 127 {
 128         return -ENOSYS;
 129 }
 130
 131 static inline void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
 132 {
 133         return;
 134 }
 135
 136 static inline int cipso_v4_doi_remove(u32 doi,
 137                                       struct netlbl_audit *audit_info)
 138 {
 139         return 0;
 140 }
 141
 142 static inline struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
 143 {
 144         return NULL;
 145 }
 146
 147 static inline int cipso_v4_doi_walk(u32 *skip_cnt,
 148                      int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
 149                      void *cb_arg)
 150 {
 151         return 0;
 152 }
 153 #endif /* CONFIG_NETLABEL */
 154
 155 /*
 156  * Label Mapping Cache Functions
 157  */
 158
 159 #ifdef CONFIG_NETLABEL
 160 void cipso_v4_cache_invalidate(void);
 161 int cipso_v4_cache_add(const unsigned char *cipso_ptr,
 162                        const struct netlbl_lsm_secattr *secattr);
 163 #else
 164 static inline void cipso_v4_cache_invalidate(void)
 165 {
 166         return;
 167 }
 168
 169 static inline int cipso_v4_cache_add(const unsigned char *cipso_ptr,
 170                                      const struct netlbl_lsm_secattr *secattr)
 171 {
 172         return 0;
 173 }
 174 #endif /* CONFIG_NETLABEL */
 175
 176 /*
 177  * Protocol Handling Functions
 178  */
 179
 180 #ifdef CONFIG_NETLABEL
 181 void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway);
 182 int cipso_v4_getattr(const unsigned char *cipso,
 183                      struct netlbl_lsm_secattr *secattr);
 184 int cipso_v4_sock_setattr(struct sock *sk,
 185                           const struct cipso_v4_doi *doi_def,
 186                           const struct netlbl_lsm_secattr *secattr,
 187                           bool sk_locked);
 188 void cipso_v4_sock_delattr(struct sock *sk);
 189 int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
 190 int cipso_v4_req_setattr(struct request_sock *req,
 191                          const struct cipso_v4_doi *doi_def,
 192                          const struct netlbl_lsm_secattr *secattr);
 193 void cipso_v4_req_delattr(struct request_sock *req);
 194 int cipso_v4_skbuff_setattr(struct sk_buff *skb,
 195                             const struct cipso_v4_doi *doi_def,
 196                             const struct netlbl_lsm_secattr *secattr);
 197 int cipso_v4_skbuff_delattr(struct sk_buff *skb);
 198 int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
 199                             struct netlbl_lsm_secattr *secattr);
 200 unsigned char *cipso_v4_optptr(const struct sk_buff *skb);
 201 int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option);
 202 #else
 203 static inline void cipso_v4_error(struct sk_buff *skb,
 204                                   int error,
 205                                   u32 gateway)
 206 {
 207         return;
 208 }
 209
 210 static inline int cipso_v4_getattr(const unsigned char *cipso,
 211                                    struct netlbl_lsm_secattr *secattr)
 212 {
 213         return -ENOSYS;
 214 }
 215
 216 static inline int cipso_v4_sock_setattr(struct sock *sk,
 217                                       const struct cipso_v4_doi *doi_def,
 218                                       const struct netlbl_lsm_secattr *secattr,
 219                                       bool sk_locked)
 220 {
 221         return -ENOSYS;
 222 }
 223
 224 static inline void cipso_v4_sock_delattr(struct sock *sk)
 225 {
 226 }
 227
 228 static inline int cipso_v4_sock_getattr(struct sock *sk,
 229                                         struct netlbl_lsm_secattr *secattr)
 230 {
 231         return -ENOSYS;
 232 }
 233
 234 static inline int cipso_v4_req_setattr(struct request_sock *req,
 235                                        const struct cipso_v4_doi *doi_def,
 236                                        const struct netlbl_lsm_secattr *secattr)
 237 {
 238         return -ENOSYS;
 239 }
 240
 241 static inline void cipso_v4_req_delattr(struct request_sock *req)
 242 {
 243         return;
 244 }
 245
 246 static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
 247                                       const struct cipso_v4_doi *doi_def,
 248                                       const struct netlbl_lsm_secattr *secattr)
 249 {
 250         return -ENOSYS;
 251 }
 252
 253 static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb)
 254 {
 255         return -ENOSYS;
 256 }
 257
 258 static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
 259                                           struct netlbl_lsm_secattr *secattr)
 260 {
 261         return -ENOSYS;
 262 }
 263
 264 static inline unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
 265 {
 266         return NULL;
 267 }
 268
 269 static inline int cipso_v4_validate(const struct sk_buff *skb,
 270                                     unsigned char **option)
 271 {
 272         unsigned char *opt = *option;
 273         unsigned char err_offset = 0;
 274         u8 opt_len = opt[1];
 275         u8 opt_iter;
 276         u8 tag_len;
 277
 278         if (opt_len < 8) {
 279                 err_offset = 1;
 280                 goto out;
 281         }
 282
 283         if (get_unaligned_be32(&opt[2]) == 0) {
 284                 err_offset = 2;
 285                 goto out;
 286         }
 287
 288         for (opt_iter = 6; opt_iter < opt_len;) {
 289                 if (opt_iter + 1 == opt_len) {
 290                         err_offset = opt_iter;
 291                         goto out;
 292                 }
 293                 tag_len = opt[opt_iter + 1];
 294                 if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
 295                         err_offset = opt_iter + 1;
 296                         goto out;
 297                 }
 298                 opt_iter += tag_len;
 299         }
 300
 301 out:
 302         *option = opt + err_offset;
 303         return err_offset;
 304
 305 }
 306 #endif /* CONFIG_NETLABEL */
 307
 308 #endif /* _CIPSO_IPV4_H */