/*
* NetLabel System
*
* The NetLabel system manages static and dynamic label mappings for network
* protocols such as CIPSO and RIPSO.
*
* Author: Paul Moore <paul.moore@hp.com>
*
*/
/*
* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#ifndef _NETLABEL_H
#define _NETLABEL_H
#include <linux/types.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <asm/atomic.h>
/*
* NetLabel - A management interface for maintaining network packet label
* mapping tables for explicit packet labling protocols.
*
* Network protocols such as CIPSO and RIPSO require a label translation layer
* to convert the label on the packet into something meaningful on the host
* machine. In the current Linux implementation these mapping tables live
* inside the kernel; NetLabel provides a mechanism for user space applications
* to manage these mapping tables.
*
* NetLabel makes use of the Generic NETLINK mechanism as a transport layer to
* send messages between kernel and user space. The general format of a
* NetLabel message is shown below:
*
* +-----------------+-------------------+--------- --- -- -
* | struct nlmsghdr | struct genlmsghdr | payload
* +-----------------+-------------------+--------- --- -- -
*
* The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal.
* The payload is dependent on the subsystem specified in the
* 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions
* should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c
* file. All of the fields in the NetLabel payload are NETLINK attributes, see
* the include/net/netlink.h file for more information on NETLINK attributes.
*
*/
/*
* NetLabel NETLINK protocol
*/
/* NetLabel NETLINK protocol version
* 1: initial version
* 2: added static labels for unlabeled connections
*/
#define NETLBL_PROTO_VERSION 2
/* NetLabel NETLINK types/families */
#define NETLBL_NLTYPE_NONE 0
#define NETLBL_NLTYPE_MGMT 1
#define NETLBL_NLTYPE_MGMT_NAME "NLBL_MGMT"
#define NETLBL_NLTYPE_RIPSO 2
#define NETLBL_NLTYPE_RIPSO_NAME "NLBL_RIPSO"
#define NETLBL_NLTYPE_CIPSOV4 3
#define NETLBL_NLTYPE_CIPSOV4_NAME "NLBL_CIPSOv4"
#define NETLBL_NLTYPE_CIPSOV6 4
#define NETLBL_NLTYPE_CIPSOV6_NAME "NLBL_CIPSOv6"
#define NETLBL_NLTYPE_UNLABELED 5
#define NETLBL_NLTYPE_UNLABELED_NAME "NLBL_UNLBL"
/*
* NetLabel - Kernel API for accessing the network packet label mappings.
*
* The following functions are provided for use by other kernel modules,
* specifically kernel LSM modules, to provide a consistent, transparent API
* for dealing with explicit packet labeling protocols such as CIPSO and
* RIPSO. The functions defined here are implemented in the
* net/netlabel/netlabel_kapi.c file.
*
*/
/* NetLabel audit information */
struct netlbl_audit {
u32 secid;
uid_t loginuid;
};
/* Domain mapping definition struct */
struct netlbl_dom_map;
/* Domain mapping operations */
int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info);
/*
* LSM security attributes
*/
/**
* struct netlbl_lsm_cache - NetLabel LSM security attribute cache
* @refcount: atomic reference counter
* @free: LSM supplied function to free the cache data
* @data: LSM supplied cache data
*
* Description:
* This structure is provided for LSMs which wish to make use of the NetLabel
* caching mechanism to store LSM specific data/attributes in the NetLabel
* cache. If the LSM has to perform a lot of translation from the NetLabel
* security attributes into it's own internal representation then the cache
* mechanism can provide a way to eliminate some or all of that translation
* overhead on a cache hit.
*
*/
struct netlbl_lsm_cache {
atomic_t refcount;
void (*free) (const void *data);
void *data;
};
/**
* struct netlbl_lsm_secattr_catmap - NetLabel LSM secattr category bitmap
* @startbit: the value of the lowest order bit in the bitmap
* @bitmap: the category bitmap
* @next: pointer to the next bitmap "node" or NULL
*
* Description:
* This structure is used to represent category bitmaps. Due to the large
* number of categories supported by most labeling protocols it is not
* practical to transfer a full bitmap internally so NetLabel adopts a sparse
* bitmap structure modeled after SELinux's ebitmap structure.
* The catmap bitmap field MUST be a power of two in length and large
* enough to hold at least 240 bits. Special care (i.e. check the code!)
* should be used when changing these values as the LSM implementation
* probably has functions which rely on the sizes of these types to speed
* processing.
*
*/
#define NETLBL_CATMAP_MAPTYPE u64
#define NETLBL_CATMAP_MAPCNT 4
#define NETLBL_CATMAP_MAPSIZE (sizeof(NETLBL_CATMAP_MAPTYPE) * 8)
#define NETLBL_CATMAP_SIZE (NETLBL_CATMAP_MAPSIZE * \
NETLBL_CATMAP_MAPCNT)
#define NETLBL_CATMAP_BIT (NETLBL_CATMAP_MAPTYPE)0x01
struct netlbl_lsm_secattr_catmap {
u32 startbit;
NETLBL_CATMAP_MAPTYPE bitmap[NETLBL_CATMAP_MAPCNT];
struct netlbl_lsm_secattr_catmap *next;
};
/**
* struct netlbl_lsm_secattr - NetLabel LSM security attributes
* @flags: indicate which attributes are contained in this structure
* @type: indicate the NLTYPE of the attributes
* @domain: the NetLabel LSM domain
* @cache: NetLabel LSM specific cache
* @attr.mls: MLS sensitivity label
* @attr.mls.cat: MLS category bitmap
* @attr.mls.lvl: MLS sensitivity level
* @attr.secid: LSM specific secid token
*
* Description:
* This structure is used to pass security attributes between NetLabel and the
* LSM modules. The flags field is used to specify which fields within the
* struct are valid and valid values can be created by bitwise OR'ing the
* NETLBL_SECATTR_* defines. The domain field is typically set by the LSM to
* specify domain specific configuration settings and is not usually used by
* NetLabel itself when returning security attributes to the LSM.
*
*/
#define NETLBL_SECATTR_NONE 0x00000000
#define NETLBL_SECATTR_DOMAIN 0x00000001
#define NETLBL_SECATTR_CACHE 0x00000002
#define NETLBL_SECATTR_MLS_LVL 0x00000004
#define NETLBL_SECATTR_MLS_CAT 0x00000008
#define NETLBL_SECATTR_SECID 0x00000010
#define NETLBL_SECATTR_CACHEABLE (NETLBL_SECATTR_MLS_LVL | \
NETLBL_SECATTR_MLS_CAT | \
NETLBL_SECATTR_SECID)
struct netlbl_lsm_secattr {
u32 flags;
u32 type;
char *domain;
struct netlbl_lsm_cache *cache;
union {
struct {
struct netlbl_lsm_secattr_catmap *cat;
u32 lvl;
} mls;
u32 secid;
} attr;
};
/*
* LSM security attribute operations (inline)
*/
/**
* netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache
* @flags: the memory allocation flags
*
* Description:
* Allocate and initialize a netlbl_lsm_cache structure. Returns a pointer
* on success, NULL on failure.
*
*/
static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags)
{
struct netlbl_lsm_cache *cache;
cache = kzalloc(sizeof(*cache), flags);
if (cache)
atomic_set(&cache->refcount, 1);
return cache;
}
/**
* netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct
* @cache: the struct to free
*
* Description:
* Frees @secattr including all of the internal buffers.
*
*/
static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache)
{
if (!atomic_dec_and_test(&cache->refcount))
return;
if (cache->free)
cache->free(cache->data);
kfree(cache);
}
/**
* netlbl_secattr_catmap_alloc - Allocate a LSM secattr catmap
* @flags: memory allocation flags
*
* Description:
* Allocate memory for a LSM secattr catmap, returns a pointer on success, NULL
* on failure.
*
*/
static inline struct netlbl_lsm_secattr_catmap *netlbl_secattr_catmap_alloc(
gfp_t flags)
{
return kzalloc(sizeof(struct netlbl_lsm_secattr_catmap), flags);
}
/**
* netlbl_secattr_catmap_free - Free a LSM secattr catmap
* @catmap: the category bitmap
*
* Description:
* Free a LSM secattr catmap.
*
*/
static inline void netlbl_secattr_catmap_free(
struct netlbl_lsm_secattr_catmap *catmap)
{
struct netlbl_lsm_secattr_catmap *iter;
do {
iter = catmap;
catmap = catmap->next;
kfree(iter);
} while (catmap);
}
/**
* netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
* @secattr: the struct to initialize
*
* Description:
* Initialize an already allocated netlbl_lsm_secattr struct.
*
*/
static inline void netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
{
memset(secattr, 0, sizeof(*secattr));
}
/**
* netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
* @secattr: the struct to clear
*
* Description:
* Destroys the @secattr struct, including freeing all of the internal buffers.
* The struct must be reset with a call to netlbl_secattr_init() before reuse.
*
*/
static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr)
{
kfree(secattr->domain);
if (secattr->flags & NETLBL_SECATTR_CACHE)
netlbl_secattr_cache_free(secattr->cache);
if (secattr->flags & NETLBL_SECATTR_MLS_CAT)
netlbl_secattr_catmap_free(secattr->attr.mls.cat);
}
/**
* netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
* @flags: the memory allocation flags
*
* Description:
* Allocate and initialize a netlbl_lsm_secattr struct. Returns a valid
* pointer on success, or NULL on failure.
*
*/
static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(gfp_t flags)
{
return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
}
/**
* netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
* @secattr: the struct to free
*
* Description:
* Frees @secattr including all of the internal buffers.
*
*/
static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr)
{
netlbl_secattr_destroy(secattr);
kfree(secattr);
}
#ifdef CONFIG_NETLABEL
/*
* LSM security attribute operations
*/
int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
u32 offset);
int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
u32 offset);
int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
u32 bit,
gfp_t flags);
int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
u32 start,
u32 end,
gfp_t flags);
/*
* LSM protocol operations (NetLabel LSM/kernel API)
*/
int netlbl_enabled(void);
int netlbl_sock_setattr(struct sock *sk,
const struct netlbl_lsm_secattr *secattr);
int netlbl_sock_getattr(struct sock *sk,
struct netlbl_lsm_secattr *secattr);
int netlbl_skbuff_getattr(const struct sk_buff *skb,
u16 family,
struct netlbl_lsm_secattr *secattr);
void netlbl_skbuff_err(struct sk_buff *skb, int error);
/*
* LSM label mapping cache operations
*/
void netlbl_cache_invalidate(void);
int netlbl_cache_add(const struct sk_buff *skb,
const struct netlbl_lsm_secattr *secattr);
#else
static inline int netlbl_secattr_catmap_walk(
struct netlbl_lsm_secattr_catmap *catmap,
u32 offset)
{
return -ENOENT;
}
static inline int netlbl_secattr_catmap_walk_rng(
struct netlbl_lsm_secattr_catmap *catmap,
u32 offset)
{
return -ENOENT;
}
static inline int netlbl_secattr_catmap_setbit(
struct netlbl_lsm_secattr_catmap *catmap,
u32 bit,
gfp_t flags)
{
return 0;
}
static inline int netlbl_secattr_catmap_setrng(
struct netlbl_lsm_secattr_catmap *catmap,
u32 start,
u32 end,
gfp_t flags)
{
return 0;
}
static inline int netlbl_enabled(void)
{
return 0;
}
static inline int netlbl_sock_setattr(struct sock *sk,
const struct netlbl_lsm_secattr *secattr)
{
return -ENOSYS;
}
static inline int netlbl_sock_getattr(struct sock *sk,
struct netlbl_lsm_secattr *secattr)
{
return -ENOSYS;
}
static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
u16 family,
struct netlbl_lsm_secattr *secattr)
{
return -ENOSYS;
}
static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
{
return;
}
static inline void netlbl_cache_invalidate(void)
{
return;
}
static inline int netlbl_cache_add(const struct sk_buff *skb,
const struct netlbl_lsm_secattr *secattr)
{
return 0;
}
#endif /* CONFIG_NETLABEL */
#endif /* _NETLABEL_H */
