66625984ca
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
1495 lines
40 KiB
C
1495 lines
40 KiB
C
/*
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* CIPSO - Commercial IP Security Option
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*
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* This is an implementation of the CIPSO 2.2 protocol as specified in
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* draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
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* FIPS-188, copies of both documents can be found in the Documentation
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* directory. While CIPSO never became a full IETF RFC standard many vendors
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* have chosen to adopt the protocol and over the years it has become a
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* de-facto standard for labeled networking.
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*
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* Author: Paul Moore <paul.moore@hp.com>
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*
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*/
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/*
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* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
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* the GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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*/
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#include <linux/init.h>
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#include <linux/types.h>
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#include <linux/rcupdate.h>
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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#include <linux/jhash.h>
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#include <net/ip.h>
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#include <net/icmp.h>
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#include <net/tcp.h>
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#include <net/netlabel.h>
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#include <net/cipso_ipv4.h>
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#include <asm/atomic.h>
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#include <asm/bug.h>
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struct cipso_v4_domhsh_entry {
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char *domain;
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u32 valid;
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struct list_head list;
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struct rcu_head rcu;
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};
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/* List of available DOI definitions */
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/* XXX - Updates should be minimal so having a single lock for the
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* cipso_v4_doi_list and the cipso_v4_doi_list->dom_list should be
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* okay. */
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/* XXX - This currently assumes a minimal number of different DOIs in use,
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* if in practice there are a lot of different DOIs this list should
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* probably be turned into a hash table or something similar so we
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* can do quick lookups. */
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static DEFINE_SPINLOCK(cipso_v4_doi_list_lock);
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static struct list_head cipso_v4_doi_list = LIST_HEAD_INIT(cipso_v4_doi_list);
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/* Label mapping cache */
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int cipso_v4_cache_enabled = 1;
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int cipso_v4_cache_bucketsize = 10;
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#define CIPSO_V4_CACHE_BUCKETBITS 7
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#define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS)
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#define CIPSO_V4_CACHE_REORDERLIMIT 10
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struct cipso_v4_map_cache_bkt {
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spinlock_t lock;
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u32 size;
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struct list_head list;
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};
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struct cipso_v4_map_cache_entry {
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u32 hash;
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unsigned char *key;
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size_t key_len;
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struct netlbl_lsm_cache *lsm_data;
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u32 activity;
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struct list_head list;
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};
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static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL;
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/* Restricted bitmap (tag #1) flags */
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int cipso_v4_rbm_optfmt = 0;
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int cipso_v4_rbm_strictvalid = 1;
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/*
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* Helper Functions
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*/
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/**
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* cipso_v4_bitmap_walk - Walk a bitmap looking for a bit
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* @bitmap: the bitmap
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* @bitmap_len: length in bits
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* @offset: starting offset
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* @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit
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*
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* Description:
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* Starting at @offset, walk the bitmap from left to right until either the
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* desired bit is found or we reach the end. Return the bit offset, -1 if
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* not found, or -2 if error.
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*/
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static int cipso_v4_bitmap_walk(const unsigned char *bitmap,
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u32 bitmap_len,
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u32 offset,
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u8 state)
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{
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u32 bit_spot;
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u32 byte_offset;
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unsigned char bitmask;
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unsigned char byte;
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/* gcc always rounds to zero when doing integer division */
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byte_offset = offset / 8;
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byte = bitmap[byte_offset];
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bit_spot = offset;
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bitmask = 0x80 >> (offset % 8);
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while (bit_spot < bitmap_len) {
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if ((state && (byte & bitmask) == bitmask) ||
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(state == 0 && (byte & bitmask) == 0))
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return bit_spot;
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bit_spot++;
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bitmask >>= 1;
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if (bitmask == 0) {
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byte = bitmap[++byte_offset];
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bitmask = 0x80;
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}
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}
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return -1;
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}
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/**
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* cipso_v4_bitmap_setbit - Sets a single bit in a bitmap
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* @bitmap: the bitmap
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* @bit: the bit
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* @state: if non-zero, set the bit (1) else clear the bit (0)
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*
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* Description:
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* Set a single bit in the bitmask. Returns zero on success, negative values
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* on error.
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*/
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static void cipso_v4_bitmap_setbit(unsigned char *bitmap,
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u32 bit,
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u8 state)
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{
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u32 byte_spot;
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u8 bitmask;
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/* gcc always rounds to zero when doing integer division */
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byte_spot = bit / 8;
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bitmask = 0x80 >> (bit % 8);
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if (state)
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bitmap[byte_spot] |= bitmask;
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else
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bitmap[byte_spot] &= ~bitmask;
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}
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/**
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* cipso_v4_doi_domhsh_free - Frees a domain list entry
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* @entry: the entry's RCU field
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*
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* Description:
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* This function is designed to be used as a callback to the call_rcu()
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* function so that the memory allocated to a domain list entry can be released
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* safely.
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*
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*/
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static void cipso_v4_doi_domhsh_free(struct rcu_head *entry)
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{
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struct cipso_v4_domhsh_entry *ptr;
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ptr = container_of(entry, struct cipso_v4_domhsh_entry, rcu);
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kfree(ptr->domain);
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kfree(ptr);
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}
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/**
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* cipso_v4_cache_entry_free - Frees a cache entry
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* @entry: the entry to free
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*
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* Description:
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* This function frees the memory associated with a cache entry including the
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* LSM cache data if there are no longer any users, i.e. reference count == 0.
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*
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*/
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static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry)
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{
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if (entry->lsm_data)
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netlbl_secattr_cache_free(entry->lsm_data);
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kfree(entry->key);
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kfree(entry);
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}
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/**
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* cipso_v4_map_cache_hash - Hashing function for the CIPSO cache
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* @key: the hash key
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* @key_len: the length of the key in bytes
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*
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* Description:
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* The CIPSO tag hashing function. Returns a 32-bit hash value.
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*
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*/
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static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len)
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{
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return jhash(key, key_len, 0);
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}
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/*
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* Label Mapping Cache Functions
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*/
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/**
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* cipso_v4_cache_init - Initialize the CIPSO cache
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*
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* Description:
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* Initializes the CIPSO label mapping cache, this function should be called
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* before any of the other functions defined in this file. Returns zero on
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* success, negative values on error.
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*
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*/
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static int cipso_v4_cache_init(void)
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{
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u32 iter;
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cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS,
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sizeof(struct cipso_v4_map_cache_bkt),
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GFP_KERNEL);
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if (cipso_v4_cache == NULL)
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return -ENOMEM;
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for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
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spin_lock_init(&cipso_v4_cache[iter].lock);
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cipso_v4_cache[iter].size = 0;
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INIT_LIST_HEAD(&cipso_v4_cache[iter].list);
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}
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return 0;
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}
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/**
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* cipso_v4_cache_invalidate - Invalidates the current CIPSO cache
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*
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* Description:
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* Invalidates and frees any entries in the CIPSO cache. Returns zero on
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* success and negative values on failure.
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*
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*/
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void cipso_v4_cache_invalidate(void)
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{
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struct cipso_v4_map_cache_entry *entry, *tmp_entry;
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u32 iter;
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for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
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spin_lock_bh(&cipso_v4_cache[iter].lock);
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list_for_each_entry_safe(entry,
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tmp_entry,
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&cipso_v4_cache[iter].list, list) {
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list_del(&entry->list);
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cipso_v4_cache_entry_free(entry);
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}
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cipso_v4_cache[iter].size = 0;
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spin_unlock_bh(&cipso_v4_cache[iter].lock);
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}
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return;
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}
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/**
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* cipso_v4_cache_check - Check the CIPSO cache for a label mapping
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* @key: the buffer to check
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* @key_len: buffer length in bytes
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* @secattr: the security attribute struct to use
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*
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* Description:
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* This function checks the cache to see if a label mapping already exists for
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* the given key. If there is a match then the cache is adjusted and the
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* @secattr struct is populated with the correct LSM security attributes. The
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* cache is adjusted in the following manner if the entry is not already the
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* first in the cache bucket:
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*
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* 1. The cache entry's activity counter is incremented
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* 2. The previous (higher ranking) entry's activity counter is decremented
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* 3. If the difference between the two activity counters is geater than
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* CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped
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*
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* Returns zero on success, -ENOENT for a cache miss, and other negative values
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* on error.
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*
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*/
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static int cipso_v4_cache_check(const unsigned char *key,
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u32 key_len,
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struct netlbl_lsm_secattr *secattr)
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{
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u32 bkt;
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struct cipso_v4_map_cache_entry *entry;
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struct cipso_v4_map_cache_entry *prev_entry = NULL;
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u32 hash;
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if (!cipso_v4_cache_enabled)
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return -ENOENT;
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hash = cipso_v4_map_cache_hash(key, key_len);
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bkt = hash & (CIPSO_V4_CACHE_BUCKETBITS - 1);
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spin_lock_bh(&cipso_v4_cache[bkt].lock);
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list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) {
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if (entry->hash == hash &&
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entry->key_len == key_len &&
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memcmp(entry->key, key, key_len) == 0) {
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entry->activity += 1;
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atomic_inc(&entry->lsm_data->refcount);
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secattr->cache = entry->lsm_data;
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secattr->flags |= NETLBL_SECATTR_CACHE;
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if (prev_entry == NULL) {
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spin_unlock_bh(&cipso_v4_cache[bkt].lock);
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return 0;
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}
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if (prev_entry->activity > 0)
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prev_entry->activity -= 1;
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if (entry->activity > prev_entry->activity &&
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entry->activity - prev_entry->activity >
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CIPSO_V4_CACHE_REORDERLIMIT) {
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__list_del(entry->list.prev, entry->list.next);
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__list_add(&entry->list,
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prev_entry->list.prev,
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&prev_entry->list);
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}
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spin_unlock_bh(&cipso_v4_cache[bkt].lock);
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return 0;
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}
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prev_entry = entry;
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}
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spin_unlock_bh(&cipso_v4_cache[bkt].lock);
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return -ENOENT;
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}
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/**
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* cipso_v4_cache_add - Add an entry to the CIPSO cache
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* @skb: the packet
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* @secattr: the packet's security attributes
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*
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* Description:
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* Add a new entry into the CIPSO label mapping cache. Add the new entry to
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* head of the cache bucket's list, if the cache bucket is out of room remove
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* the last entry in the list first. It is important to note that there is
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* currently no checking for duplicate keys. Returns zero on success,
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* negative values on failure.
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*
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*/
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int cipso_v4_cache_add(const struct sk_buff *skb,
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const struct netlbl_lsm_secattr *secattr)
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{
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int ret_val = -EPERM;
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u32 bkt;
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struct cipso_v4_map_cache_entry *entry = NULL;
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struct cipso_v4_map_cache_entry *old_entry = NULL;
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unsigned char *cipso_ptr;
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u32 cipso_ptr_len;
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if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
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return 0;
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cipso_ptr = CIPSO_V4_OPTPTR(skb);
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cipso_ptr_len = cipso_ptr[1];
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entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
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if (entry == NULL)
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return -ENOMEM;
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entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC);
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if (entry->key == NULL) {
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ret_val = -ENOMEM;
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goto cache_add_failure;
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}
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entry->key_len = cipso_ptr_len;
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entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len);
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atomic_inc(&secattr->cache->refcount);
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entry->lsm_data = secattr->cache;
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bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETBITS - 1);
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spin_lock_bh(&cipso_v4_cache[bkt].lock);
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if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
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list_add(&entry->list, &cipso_v4_cache[bkt].list);
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cipso_v4_cache[bkt].size += 1;
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} else {
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old_entry = list_entry(cipso_v4_cache[bkt].list.prev,
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struct cipso_v4_map_cache_entry, list);
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list_del(&old_entry->list);
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list_add(&entry->list, &cipso_v4_cache[bkt].list);
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cipso_v4_cache_entry_free(old_entry);
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}
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spin_unlock_bh(&cipso_v4_cache[bkt].lock);
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return 0;
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cache_add_failure:
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if (entry)
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cipso_v4_cache_entry_free(entry);
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return ret_val;
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}
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|
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/*
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* DOI List Functions
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*/
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/**
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* cipso_v4_doi_search - Searches for a DOI definition
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* @doi: the DOI to search for
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*
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* Description:
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* Search the DOI definition list for a DOI definition with a DOI value that
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* matches @doi. The caller is responsibile for calling rcu_read_[un]lock().
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* Returns a pointer to the DOI definition on success and NULL on failure.
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*/
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static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
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{
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struct cipso_v4_doi *iter;
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list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
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if (iter->doi == doi && iter->valid)
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return iter;
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return NULL;
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}
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|
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/**
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* cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine
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* @doi_def: the DOI structure
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*
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* Description:
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* The caller defines a new DOI for use by the CIPSO engine and calls this
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* function to add it to the list of acceptable domains. The caller must
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* ensure that the mapping table specified in @doi_def->map meets all of the
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* requirements of the mapping type (see cipso_ipv4.h for details). Returns
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* zero on success and non-zero on failure.
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*
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*/
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int cipso_v4_doi_add(struct cipso_v4_doi *doi_def)
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{
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u32 iter;
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if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
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return -EINVAL;
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for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
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switch (doi_def->tags[iter]) {
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case CIPSO_V4_TAG_RBITMAP:
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break;
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case CIPSO_V4_TAG_INVALID:
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if (iter == 0)
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return -EINVAL;
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break;
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default:
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return -EINVAL;
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}
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}
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doi_def->valid = 1;
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INIT_RCU_HEAD(&doi_def->rcu);
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INIT_LIST_HEAD(&doi_def->dom_list);
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rcu_read_lock();
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if (cipso_v4_doi_search(doi_def->doi) != NULL)
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goto doi_add_failure_rlock;
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spin_lock(&cipso_v4_doi_list_lock);
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if (cipso_v4_doi_search(doi_def->doi) != NULL)
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goto doi_add_failure_slock;
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list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
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spin_unlock(&cipso_v4_doi_list_lock);
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rcu_read_unlock();
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return 0;
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doi_add_failure_slock:
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spin_unlock(&cipso_v4_doi_list_lock);
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doi_add_failure_rlock:
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rcu_read_unlock();
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return -EEXIST;
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}
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|
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/**
|
|
* cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
|
|
* @doi: the DOI value
|
|
* @audit_secid: the LSM secid to use in the audit message
|
|
* @callback: the DOI cleanup/free callback
|
|
*
|
|
* Description:
|
|
* Removes a DOI definition from the CIPSO engine, @callback is called to
|
|
* free any memory. The NetLabel routines will be called to release their own
|
|
* LSM domain mappings as well as our own domain list. Returns zero on
|
|
* success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_doi_remove(u32 doi,
|
|
struct netlbl_audit *audit_info,
|
|
void (*callback) (struct rcu_head * head))
|
|
{
|
|
struct cipso_v4_doi *doi_def;
|
|
struct cipso_v4_domhsh_entry *dom_iter;
|
|
|
|
rcu_read_lock();
|
|
if (cipso_v4_doi_search(doi) != NULL) {
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (doi_def == NULL) {
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
rcu_read_unlock();
|
|
return -ENOENT;
|
|
}
|
|
doi_def->valid = 0;
|
|
list_del_rcu(&doi_def->list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list)
|
|
if (dom_iter->valid)
|
|
netlbl_domhsh_remove(dom_iter->domain,
|
|
audit_info);
|
|
cipso_v4_cache_invalidate();
|
|
rcu_read_unlock();
|
|
|
|
call_rcu(&doi_def->rcu, callback);
|
|
return 0;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return -ENOENT;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_getdef - Returns a pointer to a valid DOI definition
|
|
* @doi: the DOI value
|
|
*
|
|
* Description:
|
|
* Searches for a valid DOI definition and if one is found it is returned to
|
|
* the caller. Otherwise NULL is returned. The caller must ensure that
|
|
* rcu_read_lock() is held while accessing the returned definition.
|
|
*
|
|
*/
|
|
struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
|
|
{
|
|
return cipso_v4_doi_search(doi);
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_walk - Iterate through the DOI definitions
|
|
* @skip_cnt: skip past this number of DOI definitions, updated
|
|
* @callback: callback for each DOI definition
|
|
* @cb_arg: argument for the callback function
|
|
*
|
|
* Description:
|
|
* Iterate over the DOI definition list, skipping the first @skip_cnt entries.
|
|
* For each entry call @callback, if @callback returns a negative value stop
|
|
* 'walking' through the list and return. Updates the value in @skip_cnt upon
|
|
* return. Returns zero on success, negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_doi_walk(u32 *skip_cnt,
|
|
int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
|
|
void *cb_arg)
|
|
{
|
|
int ret_val = -ENOENT;
|
|
u32 doi_cnt = 0;
|
|
struct cipso_v4_doi *iter_doi;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
|
|
if (iter_doi->valid) {
|
|
if (doi_cnt++ < *skip_cnt)
|
|
continue;
|
|
ret_val = callback(iter_doi, cb_arg);
|
|
if (ret_val < 0) {
|
|
doi_cnt--;
|
|
goto doi_walk_return;
|
|
}
|
|
}
|
|
|
|
doi_walk_return:
|
|
rcu_read_unlock();
|
|
*skip_cnt = doi_cnt;
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_domhsh_add - Adds a domain entry to a DOI definition
|
|
* @doi_def: the DOI definition
|
|
* @domain: the domain to add
|
|
*
|
|
* Description:
|
|
* Adds the @domain to the the DOI specified by @doi_def, this function
|
|
* should only be called by external functions (i.e. NetLabel). This function
|
|
* does allocate memory. Returns zero on success, negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, const char *domain)
|
|
{
|
|
struct cipso_v4_domhsh_entry *iter;
|
|
struct cipso_v4_domhsh_entry *new_dom;
|
|
|
|
new_dom = kzalloc(sizeof(*new_dom), GFP_KERNEL);
|
|
if (new_dom == NULL)
|
|
return -ENOMEM;
|
|
if (domain) {
|
|
new_dom->domain = kstrdup(domain, GFP_KERNEL);
|
|
if (new_dom->domain == NULL) {
|
|
kfree(new_dom);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
new_dom->valid = 1;
|
|
INIT_RCU_HEAD(&new_dom->rcu);
|
|
|
|
rcu_read_lock();
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
|
list_for_each_entry_rcu(iter, &doi_def->dom_list, list)
|
|
if (iter->valid &&
|
|
((domain != NULL && iter->domain != NULL &&
|
|
strcmp(iter->domain, domain) == 0) ||
|
|
(domain == NULL && iter->domain == NULL))) {
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
rcu_read_unlock();
|
|
kfree(new_dom->domain);
|
|
kfree(new_dom);
|
|
return -EEXIST;
|
|
}
|
|
list_add_tail_rcu(&new_dom->list, &doi_def->dom_list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
rcu_read_unlock();
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_domhsh_remove - Removes a domain entry from a DOI definition
|
|
* @doi_def: the DOI definition
|
|
* @domain: the domain to remove
|
|
*
|
|
* Description:
|
|
* Removes the @domain from the DOI specified by @doi_def, this function
|
|
* should only be called by external functions (i.e. NetLabel). Returns zero
|
|
* on success and negative values on error.
|
|
*
|
|
*/
|
|
int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
|
|
const char *domain)
|
|
{
|
|
struct cipso_v4_domhsh_entry *iter;
|
|
|
|
rcu_read_lock();
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
|
list_for_each_entry_rcu(iter, &doi_def->dom_list, list)
|
|
if (iter->valid &&
|
|
((domain != NULL && iter->domain != NULL &&
|
|
strcmp(iter->domain, domain) == 0) ||
|
|
(domain == NULL && iter->domain == NULL))) {
|
|
iter->valid = 0;
|
|
list_del_rcu(&iter->list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
rcu_read_unlock();
|
|
call_rcu(&iter->rcu, cipso_v4_doi_domhsh_free);
|
|
|
|
return 0;
|
|
}
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
rcu_read_unlock();
|
|
|
|
return -ENOENT;
|
|
}
|
|
|
|
/*
|
|
* Label Mapping Functions
|
|
*/
|
|
|
|
/**
|
|
* cipso_v4_map_lvl_valid - Checks to see if the given level is understood
|
|
* @doi_def: the DOI definition
|
|
* @level: the level to check
|
|
*
|
|
* Description:
|
|
* Checks the given level against the given DOI definition and returns a
|
|
* negative value if the level does not have a valid mapping and a zero value
|
|
* if the level is defined by the DOI.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level)
|
|
{
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
return 0;
|
|
case CIPSO_V4_MAP_STD:
|
|
if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)
|
|
return 0;
|
|
break;
|
|
}
|
|
|
|
return -EFAULT;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network
|
|
* @doi_def: the DOI definition
|
|
* @host_lvl: the host MLS level
|
|
* @net_lvl: the network/CIPSO MLS level
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a local MLS level to the correct
|
|
* CIPSO level using the given DOI definition. Returns zero on success,
|
|
* negative values otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
|
|
u32 host_lvl,
|
|
u32 *net_lvl)
|
|
{
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
*net_lvl = host_lvl;
|
|
return 0;
|
|
case CIPSO_V4_MAP_STD:
|
|
if (host_lvl < doi_def->map.std->lvl.local_size) {
|
|
*net_lvl = doi_def->map.std->lvl.local[host_lvl];
|
|
return 0;
|
|
}
|
|
break;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host
|
|
* @doi_def: the DOI definition
|
|
* @net_lvl: the network/CIPSO MLS level
|
|
* @host_lvl: the host MLS level
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a CIPSO level to the correct local MLS
|
|
* level using the given DOI definition. Returns zero on success, negative
|
|
* values otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
|
|
u32 net_lvl,
|
|
u32 *host_lvl)
|
|
{
|
|
struct cipso_v4_std_map_tbl *map_tbl;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
*host_lvl = net_lvl;
|
|
return 0;
|
|
case CIPSO_V4_MAP_STD:
|
|
map_tbl = doi_def->map.std;
|
|
if (net_lvl < map_tbl->lvl.cipso_size &&
|
|
map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) {
|
|
*host_lvl = doi_def->map.std->lvl.cipso[net_lvl];
|
|
return 0;
|
|
}
|
|
break;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid
|
|
* @doi_def: the DOI definition
|
|
* @bitmap: category bitmap
|
|
* @bitmap_len: bitmap length in bytes
|
|
*
|
|
* Description:
|
|
* Checks the given category bitmap against the given DOI definition and
|
|
* returns a negative value if any of the categories in the bitmap do not have
|
|
* a valid mapping and a zero value if all of the categories are valid.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *bitmap,
|
|
u32 bitmap_len)
|
|
{
|
|
int cat = -1;
|
|
u32 bitmap_len_bits = bitmap_len * 8;
|
|
u32 cipso_cat_size;
|
|
u32 *cipso_array;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
return 0;
|
|
case CIPSO_V4_MAP_STD:
|
|
cipso_cat_size = doi_def->map.std->cat.cipso_size;
|
|
cipso_array = doi_def->map.std->cat.cipso;
|
|
for (;;) {
|
|
cat = cipso_v4_bitmap_walk(bitmap,
|
|
bitmap_len_bits,
|
|
cat + 1,
|
|
1);
|
|
if (cat < 0)
|
|
break;
|
|
if (cat >= cipso_cat_size ||
|
|
cipso_array[cat] >= CIPSO_V4_INV_CAT)
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (cat == -1)
|
|
return 0;
|
|
break;
|
|
}
|
|
|
|
return -EFAULT;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network
|
|
* @doi_def: the DOI definition
|
|
* @host_cat: the category bitmap in host format
|
|
* @host_cat_len: the length of the host's category bitmap in bytes
|
|
* @net_cat: the zero'd out category bitmap in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO bitmap in bytes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a local MLS category bitmap to the
|
|
* correct CIPSO bitmap using the given DOI definition. Returns the minimum
|
|
* size in bytes of the network bitmap on success, negative values otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *host_cat,
|
|
u32 host_cat_len,
|
|
unsigned char *net_cat,
|
|
u32 net_cat_len)
|
|
{
|
|
int host_spot = -1;
|
|
u32 net_spot;
|
|
u32 net_spot_max = 0;
|
|
u32 host_clen_bits = host_cat_len * 8;
|
|
u32 net_clen_bits = net_cat_len * 8;
|
|
u32 host_cat_size;
|
|
u32 *host_cat_array;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
net_spot_max = host_cat_len;
|
|
while (net_spot_max > 0 && host_cat[net_spot_max - 1] == 0)
|
|
net_spot_max--;
|
|
if (net_spot_max > net_cat_len)
|
|
return -EINVAL;
|
|
memcpy(net_cat, host_cat, net_spot_max);
|
|
return net_spot_max;
|
|
case CIPSO_V4_MAP_STD:
|
|
host_cat_size = doi_def->map.std->cat.local_size;
|
|
host_cat_array = doi_def->map.std->cat.local;
|
|
for (;;) {
|
|
host_spot = cipso_v4_bitmap_walk(host_cat,
|
|
host_clen_bits,
|
|
host_spot + 1,
|
|
1);
|
|
if (host_spot < 0)
|
|
break;
|
|
if (host_spot >= host_cat_size)
|
|
return -EPERM;
|
|
|
|
net_spot = host_cat_array[host_spot];
|
|
if (net_spot >= CIPSO_V4_INV_CAT)
|
|
return -EPERM;
|
|
if (net_spot >= net_clen_bits)
|
|
return -ENOSPC;
|
|
cipso_v4_bitmap_setbit(net_cat, net_spot, 1);
|
|
|
|
if (net_spot > net_spot_max)
|
|
net_spot_max = net_spot;
|
|
}
|
|
|
|
if (host_spot == -2)
|
|
return -EFAULT;
|
|
|
|
if (++net_spot_max % 8)
|
|
return net_spot_max / 8 + 1;
|
|
return net_spot_max / 8;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host
|
|
* @doi_def: the DOI definition
|
|
* @net_cat: the category bitmap in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO bitmap in bytes
|
|
* @host_cat: the zero'd out category bitmap in host format
|
|
* @host_cat_len: the length of the host's category bitmap in bytes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a CIPSO bitmap to the correct local
|
|
* MLS category bitmap using the given DOI definition. Returns the minimum
|
|
* size in bytes of the host bitmap on success, negative values otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *net_cat,
|
|
u32 net_cat_len,
|
|
unsigned char *host_cat,
|
|
u32 host_cat_len)
|
|
{
|
|
u32 host_spot;
|
|
u32 host_spot_max = 0;
|
|
int net_spot = -1;
|
|
u32 net_clen_bits = net_cat_len * 8;
|
|
u32 host_clen_bits = host_cat_len * 8;
|
|
u32 net_cat_size;
|
|
u32 *net_cat_array;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
if (net_cat_len > host_cat_len)
|
|
return -EINVAL;
|
|
memcpy(host_cat, net_cat, net_cat_len);
|
|
return net_cat_len;
|
|
case CIPSO_V4_MAP_STD:
|
|
net_cat_size = doi_def->map.std->cat.cipso_size;
|
|
net_cat_array = doi_def->map.std->cat.cipso;
|
|
for (;;) {
|
|
net_spot = cipso_v4_bitmap_walk(net_cat,
|
|
net_clen_bits,
|
|
net_spot + 1,
|
|
1);
|
|
if (net_spot < 0)
|
|
break;
|
|
if (net_spot >= net_cat_size ||
|
|
net_cat_array[net_spot] >= CIPSO_V4_INV_CAT)
|
|
return -EPERM;
|
|
|
|
host_spot = net_cat_array[net_spot];
|
|
if (host_spot >= CIPSO_V4_INV_CAT)
|
|
return -EPERM;
|
|
if (host_spot >= host_clen_bits)
|
|
return -ENOSPC;
|
|
cipso_v4_bitmap_setbit(host_cat, host_spot, 1);
|
|
|
|
if (host_spot > host_spot_max)
|
|
host_spot_max = host_spot;
|
|
}
|
|
|
|
if (net_spot == -2)
|
|
return -EFAULT;
|
|
|
|
if (++host_spot_max % 8)
|
|
return host_spot_max / 8 + 1;
|
|
return host_spot_max / 8;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Protocol Handling Functions
|
|
*/
|
|
|
|
#define CIPSO_V4_OPT_LEN_MAX 40
|
|
#define CIPSO_V4_HDR_LEN 6
|
|
|
|
/**
|
|
* cipso_v4_gentag_hdr - Generate a CIPSO option header
|
|
* @doi_def: the DOI definition
|
|
* @len: the total tag length in bytes, not including this header
|
|
* @buf: the CIPSO option buffer
|
|
*
|
|
* Description:
|
|
* Write a CIPSO header into the beginning of @buffer.
|
|
*
|
|
*/
|
|
static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def,
|
|
unsigned char *buf,
|
|
u32 len)
|
|
{
|
|
buf[0] = IPOPT_CIPSO;
|
|
buf[1] = CIPSO_V4_HDR_LEN + len;
|
|
*(__be32 *)&buf[2] = htonl(doi_def->doi);
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1)
|
|
* @doi_def: the DOI definition
|
|
* @secattr: the security attributes
|
|
* @buffer: the option buffer
|
|
* @buffer_len: length of buffer in bytes
|
|
*
|
|
* Description:
|
|
* Generate a CIPSO option using the restricted bitmap tag, tag type #1. The
|
|
* actual buffer length may be larger than the indicated size due to
|
|
* translation between host and network category bitmaps. Returns the size of
|
|
* the tag on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr,
|
|
unsigned char *buffer,
|
|
u32 buffer_len)
|
|
{
|
|
int ret_val;
|
|
u32 tag_len;
|
|
u32 level;
|
|
|
|
if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0)
|
|
return -EPERM;
|
|
|
|
ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
|
|
if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
|
|
ret_val = cipso_v4_map_cat_rbm_hton(doi_def,
|
|
secattr->mls_cat,
|
|
secattr->mls_cat_len,
|
|
&buffer[4],
|
|
buffer_len - 4);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
/* This will send packets using the "optimized" format when
|
|
* possibile as specified in section 3.4.2.6 of the
|
|
* CIPSO draft. */
|
|
if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
|
|
tag_len = 14;
|
|
else
|
|
tag_len = 4 + ret_val;
|
|
} else
|
|
tag_len = 4;
|
|
|
|
buffer[0] = 0x01;
|
|
buffer[1] = tag_len;
|
|
buffer[3] = level;
|
|
|
|
return tag_len;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag
|
|
* @doi_def: the DOI definition
|
|
* @tag: the CIPSO tag
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Parse a CIPSO restricted bitmap tag (tag type #1) and return the security
|
|
* attributes in @secattr. Return zero on success, negatives values on
|
|
* failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *tag,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
u8 tag_len = tag[1];
|
|
u32 level;
|
|
|
|
ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
secattr->mls_lvl = level;
|
|
secattr->flags |= NETLBL_SECATTR_MLS_LVL;
|
|
|
|
if (tag_len > 4) {
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
secattr->mls_cat_len = tag_len - 4;
|
|
break;
|
|
case CIPSO_V4_MAP_STD:
|
|
secattr->mls_cat_len =
|
|
doi_def->map.std->cat.local_size;
|
|
break;
|
|
}
|
|
secattr->mls_cat = kzalloc(secattr->mls_cat_len, GFP_ATOMIC);
|
|
if (secattr->mls_cat == NULL)
|
|
return -ENOMEM;
|
|
|
|
ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def,
|
|
&tag[4],
|
|
tag_len - 4,
|
|
secattr->mls_cat,
|
|
secattr->mls_cat_len);
|
|
if (ret_val < 0) {
|
|
kfree(secattr->mls_cat);
|
|
return ret_val;
|
|
} else if (ret_val > 0) {
|
|
secattr->mls_cat_len = ret_val;
|
|
secattr->flags |= NETLBL_SECATTR_MLS_CAT;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_validate - Validate a CIPSO option
|
|
* @option: the start of the option, on error it is set to point to the error
|
|
*
|
|
* Description:
|
|
* This routine is called to validate a CIPSO option, it checks all of the
|
|
* fields to ensure that they are at least valid, see the draft snippet below
|
|
* for details. If the option is valid then a zero value is returned and
|
|
* the value of @option is unchanged. If the option is invalid then a
|
|
* non-zero value is returned and @option is adjusted to point to the
|
|
* offending portion of the option. From the IETF draft ...
|
|
*
|
|
* "If any field within the CIPSO options, such as the DOI identifier, is not
|
|
* recognized the IP datagram is discarded and an ICMP 'parameter problem'
|
|
* (type 12) is generated and returned. The ICMP code field is set to 'bad
|
|
* parameter' (code 0) and the pointer is set to the start of the CIPSO field
|
|
* that is unrecognized."
|
|
*
|
|
*/
|
|
int cipso_v4_validate(unsigned char **option)
|
|
{
|
|
unsigned char *opt = *option;
|
|
unsigned char *tag;
|
|
unsigned char opt_iter;
|
|
unsigned char err_offset = 0;
|
|
u8 opt_len;
|
|
u8 tag_len;
|
|
struct cipso_v4_doi *doi_def = NULL;
|
|
u32 tag_iter;
|
|
|
|
/* caller already checks for length values that are too large */
|
|
opt_len = opt[1];
|
|
if (opt_len < 8) {
|
|
err_offset = 1;
|
|
goto validate_return;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
doi_def = cipso_v4_doi_search(ntohl(*((__be32 *)&opt[2])));
|
|
if (doi_def == NULL) {
|
|
err_offset = 2;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
opt_iter = 6;
|
|
tag = opt + opt_iter;
|
|
while (opt_iter < opt_len) {
|
|
for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];)
|
|
if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID ||
|
|
++tag_iter == CIPSO_V4_TAG_MAXCNT) {
|
|
err_offset = opt_iter;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
tag_len = tag[1];
|
|
if (tag_len > (opt_len - opt_iter)) {
|
|
err_offset = opt_iter + 1;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
switch (tag[0]) {
|
|
case CIPSO_V4_TAG_RBITMAP:
|
|
if (tag_len < 4) {
|
|
err_offset = opt_iter + 1;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
/* We are already going to do all the verification
|
|
* necessary at the socket layer so from our point of
|
|
* view it is safe to turn these checks off (and less
|
|
* work), however, the CIPSO draft says we should do
|
|
* all the CIPSO validations here but it doesn't
|
|
* really specify _exactly_ what we need to validate
|
|
* ... so, just make it a sysctl tunable. */
|
|
if (cipso_v4_rbm_strictvalid) {
|
|
if (cipso_v4_map_lvl_valid(doi_def,
|
|
tag[3]) < 0) {
|
|
err_offset = opt_iter + 3;
|
|
goto validate_return_locked;
|
|
}
|
|
if (tag_len > 4 &&
|
|
cipso_v4_map_cat_rbm_valid(doi_def,
|
|
&tag[4],
|
|
tag_len - 4) < 0) {
|
|
err_offset = opt_iter + 4;
|
|
goto validate_return_locked;
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
err_offset = opt_iter;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
tag += tag_len;
|
|
opt_iter += tag_len;
|
|
}
|
|
|
|
validate_return_locked:
|
|
rcu_read_unlock();
|
|
validate_return:
|
|
*option = opt + err_offset;
|
|
return err_offset;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_error - Send the correct reponse for a bad packet
|
|
* @skb: the packet
|
|
* @error: the error code
|
|
* @gateway: CIPSO gateway flag
|
|
*
|
|
* Description:
|
|
* Based on the error code given in @error, send an ICMP error message back to
|
|
* the originating host. From the IETF draft ...
|
|
*
|
|
* "If the contents of the CIPSO [option] are valid but the security label is
|
|
* outside of the configured host or port label range, the datagram is
|
|
* discarded and an ICMP 'destination unreachable' (type 3) is generated and
|
|
* returned. The code field of the ICMP is set to 'communication with
|
|
* destination network administratively prohibited' (code 9) or to
|
|
* 'communication with destination host administratively prohibited'
|
|
* (code 10). The value of the code is dependent on whether the originator
|
|
* of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The
|
|
* recipient of the ICMP message MUST be able to handle either value. The
|
|
* same procedure is performed if a CIPSO [option] can not be added to an
|
|
* IP packet because it is too large to fit in the IP options area."
|
|
*
|
|
* "If the error is triggered by receipt of an ICMP message, the message is
|
|
* discarded and no response is permitted (consistent with general ICMP
|
|
* processing rules)."
|
|
*
|
|
*/
|
|
void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
|
|
{
|
|
if (skb->nh.iph->protocol == IPPROTO_ICMP || error != -EACCES)
|
|
return;
|
|
|
|
if (gateway)
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0);
|
|
else
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0);
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_socket_setattr - Add a CIPSO option to a socket
|
|
* @sock: the socket
|
|
* @doi_def: the CIPSO DOI to use
|
|
* @secattr: the specific security attributes of the socket
|
|
*
|
|
* Description:
|
|
* Set the CIPSO option on the given socket using the DOI definition and
|
|
* security attributes passed to the function. This function requires
|
|
* exclusive access to @sock->sk, which means it either needs to be in the
|
|
* process of being created or locked via lock_sock(sock->sk). Returns zero on
|
|
* success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_socket_setattr(const struct socket *sock,
|
|
const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -EPERM;
|
|
u32 iter;
|
|
unsigned char *buf;
|
|
u32 buf_len = 0;
|
|
u32 opt_len;
|
|
struct ip_options *opt = NULL;
|
|
struct sock *sk;
|
|
struct inet_sock *sk_inet;
|
|
struct inet_connection_sock *sk_conn;
|
|
|
|
/* In the case of sock_create_lite(), the sock->sk field is not
|
|
* defined yet but it is not a problem as the only users of these
|
|
* "lite" PF_INET sockets are functions which do an accept() call
|
|
* afterwards so we will label the socket as part of the accept(). */
|
|
sk = sock->sk;
|
|
if (sk == NULL)
|
|
return 0;
|
|
|
|
/* We allocate the maximum CIPSO option size here so we are probably
|
|
* being a little wasteful, but it makes our life _much_ easier later
|
|
* on and after all we are only talking about 40 bytes. */
|
|
buf_len = CIPSO_V4_OPT_LEN_MAX;
|
|
buf = kmalloc(buf_len, GFP_ATOMIC);
|
|
if (buf == NULL) {
|
|
ret_val = -ENOMEM;
|
|
goto socket_setattr_failure;
|
|
}
|
|
|
|
/* XXX - This code assumes only one tag per CIPSO option which isn't
|
|
* really a good assumption to make but since we only support the MAC
|
|
* tags right now it is a safe assumption. */
|
|
iter = 0;
|
|
do {
|
|
memset(buf, 0, buf_len);
|
|
switch (doi_def->tags[iter]) {
|
|
case CIPSO_V4_TAG_RBITMAP:
|
|
ret_val = cipso_v4_gentag_rbm(doi_def,
|
|
secattr,
|
|
&buf[CIPSO_V4_HDR_LEN],
|
|
buf_len - CIPSO_V4_HDR_LEN);
|
|
break;
|
|
default:
|
|
ret_val = -EPERM;
|
|
goto socket_setattr_failure;
|
|
}
|
|
|
|
iter++;
|
|
} while (ret_val < 0 &&
|
|
iter < CIPSO_V4_TAG_MAXCNT &&
|
|
doi_def->tags[iter] != CIPSO_V4_TAG_INVALID);
|
|
if (ret_val < 0)
|
|
goto socket_setattr_failure;
|
|
cipso_v4_gentag_hdr(doi_def, buf, ret_val);
|
|
buf_len = CIPSO_V4_HDR_LEN + ret_val;
|
|
|
|
/* We can't use ip_options_get() directly because it makes a call to
|
|
* ip_options_get_alloc() which allocates memory with GFP_KERNEL and
|
|
* we won't always have CAP_NET_RAW even though we _always_ want to
|
|
* set the IPOPT_CIPSO option. */
|
|
opt_len = (buf_len + 3) & ~3;
|
|
opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
|
|
if (opt == NULL) {
|
|
ret_val = -ENOMEM;
|
|
goto socket_setattr_failure;
|
|
}
|
|
memcpy(opt->__data, buf, buf_len);
|
|
opt->optlen = opt_len;
|
|
opt->is_data = 1;
|
|
opt->cipso = sizeof(struct iphdr);
|
|
kfree(buf);
|
|
buf = NULL;
|
|
|
|
sk_inet = inet_sk(sk);
|
|
if (sk_inet->is_icsk) {
|
|
sk_conn = inet_csk(sk);
|
|
if (sk_inet->opt)
|
|
sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen;
|
|
sk_conn->icsk_ext_hdr_len += opt->optlen;
|
|
sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
|
|
}
|
|
opt = xchg(&sk_inet->opt, opt);
|
|
kfree(opt);
|
|
|
|
return 0;
|
|
|
|
socket_setattr_failure:
|
|
kfree(buf);
|
|
kfree(opt);
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_sock_getattr - Get the security attributes from a sock
|
|
* @sk: the sock
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Query @sk to see if there is a CIPSO option attached to the sock and if
|
|
* there is return the CIPSO security attributes in @secattr. This function
|
|
* requires that @sk be locked, or privately held, but it does not do any
|
|
* locking itself. Returns zero on success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -ENOMSG;
|
|
struct inet_sock *sk_inet;
|
|
unsigned char *cipso_ptr;
|
|
u32 doi;
|
|
struct cipso_v4_doi *doi_def;
|
|
|
|
sk_inet = inet_sk(sk);
|
|
if (sk_inet->opt == NULL || sk_inet->opt->cipso == 0)
|
|
return -ENOMSG;
|
|
cipso_ptr = sk_inet->opt->__data + sk_inet->opt->cipso -
|
|
sizeof(struct iphdr);
|
|
ret_val = cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr);
|
|
if (ret_val == 0)
|
|
return ret_val;
|
|
|
|
doi = ntohl(*(__be32 *)&cipso_ptr[2]);
|
|
rcu_read_lock();
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (doi_def == NULL) {
|
|
rcu_read_unlock();
|
|
return -ENOMSG;
|
|
}
|
|
|
|
/* XXX - This code assumes only one tag per CIPSO option which isn't
|
|
* really a good assumption to make but since we only support the MAC
|
|
* tags right now it is a safe assumption. */
|
|
switch (cipso_ptr[6]) {
|
|
case CIPSO_V4_TAG_RBITMAP:
|
|
ret_val = cipso_v4_parsetag_rbm(doi_def,
|
|
&cipso_ptr[6],
|
|
secattr);
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_socket_getattr - Get the security attributes from a socket
|
|
* @sock: the socket
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Query @sock to see if there is a CIPSO option attached to the socket and if
|
|
* there is return the CIPSO security attributes in @secattr. Returns zero on
|
|
* success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_socket_getattr(const struct socket *sock,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
|
|
lock_sock(sock->sk);
|
|
ret_val = cipso_v4_sock_getattr(sock->sk, secattr);
|
|
release_sock(sock->sk);
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option
|
|
* @skb: the packet
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Parse the given packet's CIPSO option and return the security attributes.
|
|
* Returns zero on success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -ENOMSG;
|
|
unsigned char *cipso_ptr;
|
|
u32 doi;
|
|
struct cipso_v4_doi *doi_def;
|
|
|
|
cipso_ptr = CIPSO_V4_OPTPTR(skb);
|
|
if (cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr) == 0)
|
|
return 0;
|
|
|
|
doi = ntohl(*(__be32 *)&cipso_ptr[2]);
|
|
rcu_read_lock();
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (doi_def == NULL)
|
|
goto skbuff_getattr_return;
|
|
|
|
/* XXX - This code assumes only one tag per CIPSO option which isn't
|
|
* really a good assumption to make but since we only support the MAC
|
|
* tags right now it is a safe assumption. */
|
|
switch (cipso_ptr[6]) {
|
|
case CIPSO_V4_TAG_RBITMAP:
|
|
ret_val = cipso_v4_parsetag_rbm(doi_def,
|
|
&cipso_ptr[6],
|
|
secattr);
|
|
break;
|
|
}
|
|
|
|
skbuff_getattr_return:
|
|
rcu_read_unlock();
|
|
return ret_val;
|
|
}
|
|
|
|
/*
|
|
* Setup Functions
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|
*/
|
|
|
|
/**
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|
* cipso_v4_init - Initialize the CIPSO module
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|
*
|
|
* Description:
|
|
* Initialize the CIPSO module and prepare it for use. Returns zero on success
|
|
* and negative values on failure.
|
|
*
|
|
*/
|
|
static int __init cipso_v4_init(void)
|
|
{
|
|
int ret_val;
|
|
|
|
ret_val = cipso_v4_cache_init();
|
|
if (ret_val != 0)
|
|
panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n",
|
|
ret_val);
|
|
|
|
return 0;
|
|
}
|
|
|
|
subsys_initcall(cipso_v4_init);
|