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
  38 /*
  39  * NetLabel - A management interface for maintaining network packet label
  40  *            mapping tables for explicit packet labling protocols.
  41  *
  42  * Network protocols such as CIPSO and RIPSO require a label translation layer
  43  * to convert the label on the packet into something meaningful on the host
  44  * machine.  In the current Linux implementation these mapping tables live
  45  * inside the kernel; NetLabel provides a mechanism for user space applications
  46  * to manage these mapping tables.
  47  *
  48  * NetLabel makes use of the Generic NETLINK mechanism as a transport layer to
  49  * send messages between kernel and user space.  The general format of a
  50  * NetLabel message is shown below:
  51  *
  52  *  +-----------------+-------------------+--------- --- -- -
  53  *  | struct nlmsghdr | struct genlmsghdr | payload
  54  *  +-----------------+-------------------+--------- --- -- -
  55  *
  56  * The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal.
  57  * The payload is dependent on the subsystem specified in the
  58  * 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions
  59  * should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c
  60  * file.  All of the fields in the NetLabel payload are NETLINK attributes, see
  61  * the include/net/netlink.h file for more information on NETLINK attributes.
  62  *
  63  */
  64
  65 /*
  66  * NetLabel NETLINK protocol
  67  */
  68
  69 #define NETLBL_PROTO_VERSION            1
  70
  71 /* NetLabel NETLINK types/families */
  72 #define NETLBL_NLTYPE_NONE              0
  73 #define NETLBL_NLTYPE_MGMT              1
  74 #define NETLBL_NLTYPE_MGMT_NAME         "NLBL_MGMT"
  75 #define NETLBL_NLTYPE_RIPSO             2
  76 #define NETLBL_NLTYPE_RIPSO_NAME        "NLBL_RIPSO"
  77 #define NETLBL_NLTYPE_CIPSOV4           3
  78 #define NETLBL_NLTYPE_CIPSOV4_NAME      "NLBL_CIPSOv4"
  79 #define NETLBL_NLTYPE_CIPSOV6           4
  80 #define NETLBL_NLTYPE_CIPSOV6_NAME      "NLBL_CIPSOv6"
  81 #define NETLBL_NLTYPE_UNLABELED         5
  82 #define NETLBL_NLTYPE_UNLABELED_NAME    "NLBL_UNLBL"
  83
  84 /*
  85  * NetLabel - Kernel API for accessing the network packet label mappings.
  86  *
  87  * The following functions are provided for use by other kernel modules,
  88  * specifically kernel LSM modules, to provide a consistent, transparent API
  89  * for dealing with explicit packet labeling protocols such as CIPSO and
  90  * RIPSO.  The functions defined here are implemented in the
  91  * net/netlabel/netlabel_kapi.c file.
  92  *
  93  */
  94
  95 /* Domain mapping definition struct */
  96 struct netlbl_dom_map;
  97
  98 /* Domain mapping operations */
  99 int netlbl_domhsh_remove(const char *domain, u32 audit_secid);
 100
 101 /* LSM security attributes */
 102 struct netlbl_lsm_cache {
 103         void (*free) (const void *data);
 104         void *data;
 105 };
 106 struct netlbl_lsm_secattr {
 107         char *domain;
 108
 109         u32 mls_lvl;
 110         u32 mls_lvl_vld;
 111         unsigned char *mls_cat;
 112         size_t mls_cat_len;
 113
 114         struct netlbl_lsm_cache cache;
 115 };
 116
 117 /*
 118  * LSM security attribute operations
 119  */
 120
 121
 122 /**
 123  * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
 124  * @secattr: the struct to initialize
 125  *
 126  * Description:
 127  * Initialize an already allocated netlbl_lsm_secattr struct.  Returns zero on
 128  * success, negative values on error.
 129  *
 130  */
 131 static inline int netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
 132 {
 133         memset(secattr, 0, sizeof(*secattr));
 134         return 0;
 135 }
 136
 137 /**
 138  * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
 139  * @secattr: the struct to clear
 140  * @clear_cache: cache clear flag
 141  *
 142  * Description:
 143  * Destroys the @secattr struct, including freeing all of the internal buffers.
 144  * If @clear_cache is true then free the cache fields, otherwise leave them
 145  * intact.  The struct must be reset with a call to netlbl_secattr_init()
 146  * before reuse.
 147  *
 148  */
 149 static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr,
 150                                           u32 clear_cache)
 151 {
 152         if (clear_cache && secattr->cache.data != NULL && secattr->cache.free)
 153                 secattr->cache.free(secattr->cache.data);
 154         kfree(secattr->domain);
 155         kfree(secattr->mls_cat);
 156 }
 157
 158 /**
 159  * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
 160  * @flags: the memory allocation flags
 161  *
 162  * Description:
 163  * Allocate and initialize a netlbl_lsm_secattr struct.  Returns a valid
 164  * pointer on success, or NULL on failure.
 165  *
 166  */
 167 static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(int flags)
 168 {
 169         return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
 170 }
 171
 172 /**
 173  * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
 174  * @secattr: the struct to free
 175  * @clear_cache: cache clear flag
 176  *
 177  * Description:
 178  * Frees @secattr including all of the internal buffers.  If @clear_cache is
 179  * true then free the cache fields, otherwise leave them intact.
 180  *
 181  */
 182 static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr,
 183                                        u32 clear_cache)
 184 {
 185         netlbl_secattr_destroy(secattr, clear_cache);
 186         kfree(secattr);
 187 }
 188
 189 /*
 190  * LSM protocol operations
 191  */
 192
 193 #ifdef CONFIG_NETLABEL
 194 int netlbl_socket_setattr(const struct socket *sock,
 195                           const struct netlbl_lsm_secattr *secattr);
 196 int netlbl_sock_getattr(struct sock *sk,
 197                         struct netlbl_lsm_secattr *secattr);
 198 int netlbl_socket_getattr(const struct socket *sock,
 199                           struct netlbl_lsm_secattr *secattr);
 200 int netlbl_skbuff_getattr(const struct sk_buff *skb,
 201                           struct netlbl_lsm_secattr *secattr);
 202 void netlbl_skbuff_err(struct sk_buff *skb, int error);
 203 #else
 204 static inline int netlbl_socket_setattr(const struct socket *sock,
 205                                      const struct netlbl_lsm_secattr *secattr)
 206 {
 207         return -ENOSYS;
 208 }
 209
 210 static inline int netlbl_sock_getattr(struct sock *sk,
 211                                       struct netlbl_lsm_secattr *secattr)
 212 {
 213         return -ENOSYS;
 214 }
 215
 216 static inline int netlbl_socket_getattr(const struct socket *sock,
 217                                         struct netlbl_lsm_secattr *secattr)
 218 {
 219         return -ENOSYS;
 220 }
 221
 222 static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
 223                                         struct netlbl_lsm_secattr *secattr)
 224 {
 225         return -ENOSYS;
 226 }
 227
 228 static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
 229 {
 230         return;
 231 }
 232 #endif /* CONFIG_NETLABEL */
 233
 234 /*
 235  * LSM label mapping cache operations
 236  */
 237
 238 #ifdef CONFIG_NETLABEL
 239 void netlbl_cache_invalidate(void);
 240 int netlbl_cache_add(const struct sk_buff *skb,
 241                      const struct netlbl_lsm_secattr *secattr);
 242 #else
 243 static inline void netlbl_cache_invalidate(void)
 244 {
 245         return;
 246 }
 247
 248 static inline int netlbl_cache_add(const struct sk_buff *skb,
 249                                    const struct netlbl_lsm_secattr *secattr)
 250 {
 251         return 0;
 252 }
 253 #endif /* CONFIG_NETLABEL */
 254
 255 #endif /* _NETLABEL_H */