include/net/netlabel.h

   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 struct netlbl_lsm_secattr {
 115         char *domain;
 116
 117         u32 mls_lvl;
 118         u32 mls_lvl_vld;
 119         unsigned char *mls_cat;
 120         size_t mls_cat_len;
 121
 122         struct netlbl_lsm_cache *cache;
 123 };
 124
 125 /*
 126  * LSM security attribute operations
 127  */
 128
 129
 130 /**
 131  * netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache
 132  * @flags: the memory allocation flags
 133  *
 134  * Description:
 135  * Allocate and initialize a netlbl_lsm_cache structure.  Returns a pointer
 136  * on success, NULL on failure.
 137  *
 138  */
 139 static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags)
 140 {
 141         struct netlbl_lsm_cache *cache;
 142
 143         cache = kzalloc(sizeof(*cache), flags);
 144         if (cache)
 145                 atomic_set(&cache->refcount, 1);
 146         return cache;
 147 }
 148
 149 /**
 150  * netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct
 151  * @cache: the struct to free
 152  *
 153  * Description:
 154  * Frees @secattr including all of the internal buffers.
 155  *
 156  */
 157 static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache)
 158 {
 159         if (!atomic_dec_and_test(&cache->refcount))
 160                 return;
 161
 162         if (cache->free)
 163                 cache->free(cache->data);
 164         kfree(cache);
 165 }
 166
 167 /**
 168  * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
 169  * @secattr: the struct to initialize
 170  *
 171  * Description:
 172  * Initialize an already allocated netlbl_lsm_secattr struct.  Returns zero on
 173  * success, negative values on error.
 174  *
 175  */
 176 static inline int netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
 177 {
 178         memset(secattr, 0, sizeof(*secattr));
 179         return 0;
 180 }
 181
 182 /**
 183  * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
 184  * @secattr: the struct to clear
 185  *
 186  * Description:
 187  * Destroys the @secattr struct, including freeing all of the internal buffers.
 188  * The struct must be reset with a call to netlbl_secattr_init() before reuse.
 189  *
 190  */
 191 static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr)
 192 {
 193         if (secattr->cache)
 194                 netlbl_secattr_cache_free(secattr->cache);
 195         kfree(secattr->domain);
 196         kfree(secattr->mls_cat);
 197 }
 198
 199 /**
 200  * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
 201  * @flags: the memory allocation flags
 202  *
 203  * Description:
 204  * Allocate and initialize a netlbl_lsm_secattr struct.  Returns a valid
 205  * pointer on success, or NULL on failure.
 206  *
 207  */
 208 static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(int flags)
 209 {
 210         return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
 211 }
 212
 213 /**
 214  * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
 215  * @secattr: the struct to free
 216  *
 217  * Description:
 218  * Frees @secattr including all of the internal buffers.
 219  *
 220  */
 221 static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr)
 222 {
 223         netlbl_secattr_destroy(secattr);
 224         kfree(secattr);
 225 }
 226
 227 /*
 228  * LSM protocol operations
 229  */
 230
 231 #ifdef CONFIG_NETLABEL
 232 int netlbl_socket_setattr(const struct socket *sock,
 233                           const struct netlbl_lsm_secattr *secattr);
 234 int netlbl_sock_getattr(struct sock *sk,
 235                         struct netlbl_lsm_secattr *secattr);
 236 int netlbl_socket_getattr(const struct socket *sock,
 237                           struct netlbl_lsm_secattr *secattr);
 238 int netlbl_skbuff_getattr(const struct sk_buff *skb,
 239                           struct netlbl_lsm_secattr *secattr);
 240 void netlbl_skbuff_err(struct sk_buff *skb, int error);
 241 #else
 242 static inline int netlbl_socket_setattr(const struct socket *sock,
 243                                      const struct netlbl_lsm_secattr *secattr)
 244 {
 245         return -ENOSYS;
 246 }
 247
 248 static inline int netlbl_sock_getattr(struct sock *sk,
 249                                       struct netlbl_lsm_secattr *secattr)
 250 {
 251         return -ENOSYS;
 252 }
 253
 254 static inline int netlbl_socket_getattr(const struct socket *sock,
 255                                         struct netlbl_lsm_secattr *secattr)
 256 {
 257         return -ENOSYS;
 258 }
 259
 260 static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
 261                                         struct netlbl_lsm_secattr *secattr)
 262 {
 263         return -ENOSYS;
 264 }
 265
 266 static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
 267 {
 268         return;
 269 }
 270 #endif /* CONFIG_NETLABEL */
 271
 272 /*
 273  * LSM label mapping cache operations
 274  */
 275
 276 #ifdef CONFIG_NETLABEL
 277 void netlbl_cache_invalidate(void);
 278 int netlbl_cache_add(const struct sk_buff *skb,
 279                      const struct netlbl_lsm_secattr *secattr);
 280 #else
 281 static inline void netlbl_cache_invalidate(void)
 282 {
 283         return;
 284 }
 285
 286 static inline int netlbl_cache_add(const struct sk_buff *skb,
 287                                    const struct netlbl_lsm_secattr *secattr)
 288 {
 289         return 0;
 290 }
 291 #endif /* CONFIG_NETLABEL */
 292
 293 #endif /* _NETLABEL_H */