mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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076ed3da0c
commit 40413955ee
("Cipso: cipso_v4_optptr enter infinite loop") fixed
a possible infinite loop in the IP option parsing of CIPSO. The fix
assumes that ip_options_compile filtered out all zero length options and
that no other one-byte options beside IPOPT_END and IPOPT_NOOP exist.
While this assumption currently holds true, add explicit checks for zero
length and invalid length options to be safe for the future. Even though
ip_options_compile should have validated the options, the introduction of
new one-byte options can still confuse this code without the additional
checks.
Signed-off-by: Stefan Nuernberger <snu@amazon.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Simon Veith <sveith@amazon.de>
Cc: stable@vger.kernel.org
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2294 lines
61 KiB
C
2294 lines
61 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. 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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* The CIPSO draft specification can be found in the kernel's Documentation
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* directory as well as the following URL:
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* http://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt
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* The FIPS-188 specification can be found at the following URL:
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* http://www.itl.nist.gov/fipspubs/fip188.htm
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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, 2008
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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, see <http://www.gnu.org/licenses/>.
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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 <linux/audit.h>
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#include <linux/slab.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 <linux/atomic.h>
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#include <linux/bug.h>
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#include <asm/unaligned.h>
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/* List of available DOI definitions */
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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 LIST_HEAD(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;
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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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* Protocol Constants
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*/
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/* Maximum size of the CIPSO IP option, derived from the fact that the maximum
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* IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */
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#define CIPSO_V4_OPT_LEN_MAX 40
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/* Length of the base CIPSO option, this includes the option type (1 byte), the
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* option length (1 byte), and the DOI (4 bytes). */
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#define CIPSO_V4_HDR_LEN 6
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/* Base length of the restrictive category bitmap tag (tag #1). */
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#define CIPSO_V4_TAG_RBM_BLEN 4
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/* Base length of the enumerated category tag (tag #2). */
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#define CIPSO_V4_TAG_ENUM_BLEN 4
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/* Base length of the ranged categories bitmap tag (tag #5). */
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#define CIPSO_V4_TAG_RNG_BLEN 4
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/* The maximum number of category ranges permitted in the ranged category tag
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* (tag #5). You may note that the IETF draft states that the maximum number
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* of category ranges is 7, but if the low end of the last category range is
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* zero then it is possible to fit 8 category ranges because the zero should
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* be omitted. */
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#define CIPSO_V4_TAG_RNG_CAT_MAX 8
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/* Base length of the local tag (non-standard tag).
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* Tag definition (may change between kernel versions)
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*
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* 0 8 16 24 32
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* +----------+----------+----------+----------+
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* | 10000000 | 00000110 | 32-bit secid value |
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* +----------+----------+----------+----------+
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* | in (host byte order)|
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* +----------+----------+
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*
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*/
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#define CIPSO_V4_TAG_LOC_BLEN 6
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/*
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* Helper Functions
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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 __init 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)
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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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}
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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_BUCKETS - 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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refcount_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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secattr->type = NETLBL_NLTYPE_CIPSOV4;
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if (!prev_entry) {
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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 unsigned char *cipso_ptr,
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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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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_len = cipso_ptr[1];
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entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
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if (!entry)
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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) {
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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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refcount_inc(&secattr->cache->refcount);
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entry->lsm_data = secattr->cache;
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bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 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 responsible 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 && refcount_read(&iter->refcount))
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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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* @audit_info: NetLabel audit information
|
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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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int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
|
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struct netlbl_audit *audit_info)
|
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{
|
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int ret_val = -EINVAL;
|
|
u32 iter;
|
|
u32 doi;
|
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u32 doi_type;
|
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struct audit_buffer *audit_buf;
|
|
|
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doi = doi_def->doi;
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doi_type = doi_def->type;
|
|
|
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if (doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
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goto doi_add_return;
|
|
for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
|
|
switch (doi_def->tags[iter]) {
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case CIPSO_V4_TAG_RBITMAP:
|
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break;
|
|
case CIPSO_V4_TAG_RANGE:
|
|
case CIPSO_V4_TAG_ENUM:
|
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if (doi_def->type != CIPSO_V4_MAP_PASS)
|
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goto doi_add_return;
|
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break;
|
|
case CIPSO_V4_TAG_LOCAL:
|
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if (doi_def->type != CIPSO_V4_MAP_LOCAL)
|
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goto doi_add_return;
|
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break;
|
|
case CIPSO_V4_TAG_INVALID:
|
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if (iter == 0)
|
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goto doi_add_return;
|
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break;
|
|
default:
|
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goto doi_add_return;
|
|
}
|
|
}
|
|
|
|
refcount_set(&doi_def->refcount, 1);
|
|
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
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if (cipso_v4_doi_search(doi_def->doi)) {
|
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spin_unlock(&cipso_v4_doi_list_lock);
|
|
ret_val = -EEXIST;
|
|
goto doi_add_return;
|
|
}
|
|
list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
ret_val = 0;
|
|
|
|
doi_add_return:
|
|
audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info);
|
|
if (audit_buf) {
|
|
const char *type_str;
|
|
switch (doi_type) {
|
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case CIPSO_V4_MAP_TRANS:
|
|
type_str = "trans";
|
|
break;
|
|
case CIPSO_V4_MAP_PASS:
|
|
type_str = "pass";
|
|
break;
|
|
case CIPSO_V4_MAP_LOCAL:
|
|
type_str = "local";
|
|
break;
|
|
default:
|
|
type_str = "(unknown)";
|
|
}
|
|
audit_log_format(audit_buf,
|
|
" cipso_doi=%u cipso_type=%s res=%u",
|
|
doi, type_str, ret_val == 0 ? 1 : 0);
|
|
audit_log_end(audit_buf);
|
|
}
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_free - Frees a DOI definition
|
|
* @doi_def: the DOI definition
|
|
*
|
|
* Description:
|
|
* This function frees all of the memory associated with a DOI definition.
|
|
*
|
|
*/
|
|
void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
|
|
{
|
|
if (!doi_def)
|
|
return;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_TRANS:
|
|
kfree(doi_def->map.std->lvl.cipso);
|
|
kfree(doi_def->map.std->lvl.local);
|
|
kfree(doi_def->map.std->cat.cipso);
|
|
kfree(doi_def->map.std->cat.local);
|
|
break;
|
|
}
|
|
kfree(doi_def);
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
|
|
* @entry: the entry's RCU field
|
|
*
|
|
* Description:
|
|
* This function is designed to be used as a callback to the call_rcu()
|
|
* function so that the memory allocated to the DOI definition can be released
|
|
* safely.
|
|
*
|
|
*/
|
|
static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
|
|
{
|
|
struct cipso_v4_doi *doi_def;
|
|
|
|
doi_def = container_of(entry, struct cipso_v4_doi, rcu);
|
|
cipso_v4_doi_free(doi_def);
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
*
|
|
* Description:
|
|
* Removes a DOI definition from the CIPSO engine. 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)
|
|
{
|
|
int ret_val;
|
|
struct cipso_v4_doi *doi_def;
|
|
struct audit_buffer *audit_buf;
|
|
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (!doi_def) {
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
ret_val = -ENOENT;
|
|
goto doi_remove_return;
|
|
}
|
|
if (!refcount_dec_and_test(&doi_def->refcount)) {
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
ret_val = -EBUSY;
|
|
goto doi_remove_return;
|
|
}
|
|
list_del_rcu(&doi_def->list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
|
|
cipso_v4_cache_invalidate();
|
|
call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
|
|
ret_val = 0;
|
|
|
|
doi_remove_return:
|
|
audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info);
|
|
if (audit_buf) {
|
|
audit_log_format(audit_buf,
|
|
" cipso_doi=%u res=%u",
|
|
doi, ret_val == 0 ? 1 : 0);
|
|
audit_log_end(audit_buf);
|
|
}
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_getdef - Returns a reference 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 and the DOI
|
|
* definition reference count is decremented when the caller is done.
|
|
*
|
|
*/
|
|
struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
|
|
{
|
|
struct cipso_v4_doi *doi_def;
|
|
|
|
rcu_read_lock();
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (!doi_def)
|
|
goto doi_getdef_return;
|
|
if (!refcount_inc_not_zero(&doi_def->refcount))
|
|
doi_def = NULL;
|
|
|
|
doi_getdef_return:
|
|
rcu_read_unlock();
|
|
return doi_def;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_doi_putdef - Releases a reference for the given DOI definition
|
|
* @doi_def: the DOI definition
|
|
*
|
|
* Description:
|
|
* Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
|
|
*
|
|
*/
|
|
void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
|
|
{
|
|
if (!doi_def)
|
|
return;
|
|
|
|
if (!refcount_dec_and_test(&doi_def->refcount))
|
|
return;
|
|
spin_lock(&cipso_v4_doi_list_lock);
|
|
list_del_rcu(&doi_def->list);
|
|
spin_unlock(&cipso_v4_doi_list_lock);
|
|
|
|
cipso_v4_cache_invalidate();
|
|
call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
|
|
}
|
|
|
|
/**
|
|
* 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 (refcount_read(&iter_doi->refcount) > 0) {
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* 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_TRANS:
|
|
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_TRANS:
|
|
if (host_lvl < doi_def->map.std->lvl.local_size &&
|
|
doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
|
|
*net_lvl = doi_def->map.std->lvl.local[host_lvl];
|
|
return 0;
|
|
}
|
|
return -EPERM;
|
|
}
|
|
|
|
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_TRANS:
|
|
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;
|
|
}
|
|
return -EPERM;
|
|
}
|
|
|
|
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_TRANS:
|
|
cipso_cat_size = doi_def->map.std->cat.cipso_size;
|
|
cipso_array = doi_def->map.std->cat.cipso;
|
|
for (;;) {
|
|
cat = netlbl_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
|
|
* @secattr: the security attributes
|
|
* @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 struct netlbl_lsm_secattr *secattr,
|
|
unsigned char *net_cat,
|
|
u32 net_cat_len)
|
|
{
|
|
int host_spot = -1;
|
|
u32 net_spot = CIPSO_V4_INV_CAT;
|
|
u32 net_spot_max = 0;
|
|
u32 net_clen_bits = net_cat_len * 8;
|
|
u32 host_cat_size = 0;
|
|
u32 *host_cat_array = NULL;
|
|
|
|
if (doi_def->type == CIPSO_V4_MAP_TRANS) {
|
|
host_cat_size = doi_def->map.std->cat.local_size;
|
|
host_cat_array = doi_def->map.std->cat.local;
|
|
}
|
|
|
|
for (;;) {
|
|
host_spot = netlbl_catmap_walk(secattr->attr.mls.cat,
|
|
host_spot + 1);
|
|
if (host_spot < 0)
|
|
break;
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
net_spot = host_spot;
|
|
break;
|
|
case CIPSO_V4_MAP_TRANS:
|
|
if (host_spot >= host_cat_size)
|
|
return -EPERM;
|
|
net_spot = host_cat_array[host_spot];
|
|
if (net_spot >= CIPSO_V4_INV_CAT)
|
|
return -EPERM;
|
|
break;
|
|
}
|
|
if (net_spot >= net_clen_bits)
|
|
return -ENOSPC;
|
|
netlbl_bitmap_setbit(net_cat, net_spot, 1);
|
|
|
|
if (net_spot > net_spot_max)
|
|
net_spot_max = net_spot;
|
|
}
|
|
|
|
if (++net_spot_max % 8)
|
|
return net_spot_max / 8 + 1;
|
|
return net_spot_max / 8;
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a CIPSO bitmap to the correct local
|
|
* MLS category bitmap using the given DOI definition. Returns zero on
|
|
* success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *net_cat,
|
|
u32 net_cat_len,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
int net_spot = -1;
|
|
u32 host_spot = CIPSO_V4_INV_CAT;
|
|
u32 net_clen_bits = net_cat_len * 8;
|
|
u32 net_cat_size = 0;
|
|
u32 *net_cat_array = NULL;
|
|
|
|
if (doi_def->type == CIPSO_V4_MAP_TRANS) {
|
|
net_cat_size = doi_def->map.std->cat.cipso_size;
|
|
net_cat_array = doi_def->map.std->cat.cipso;
|
|
}
|
|
|
|
for (;;) {
|
|
net_spot = netlbl_bitmap_walk(net_cat,
|
|
net_clen_bits,
|
|
net_spot + 1,
|
|
1);
|
|
if (net_spot < 0) {
|
|
if (net_spot == -2)
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
switch (doi_def->type) {
|
|
case CIPSO_V4_MAP_PASS:
|
|
host_spot = net_spot;
|
|
break;
|
|
case CIPSO_V4_MAP_TRANS:
|
|
if (net_spot >= net_cat_size)
|
|
return -EPERM;
|
|
host_spot = net_cat_array[net_spot];
|
|
if (host_spot >= CIPSO_V4_INV_CAT)
|
|
return -EPERM;
|
|
break;
|
|
}
|
|
ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat,
|
|
host_spot,
|
|
GFP_ATOMIC);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid
|
|
* @doi_def: the DOI definition
|
|
* @enumcat: category list
|
|
* @enumcat_len: length of the category list in bytes
|
|
*
|
|
* Description:
|
|
* Checks the given categories against the given DOI definition and returns a
|
|
* negative value if any of the categories do not have a valid mapping and a
|
|
* zero value if all of the categories are valid.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *enumcat,
|
|
u32 enumcat_len)
|
|
{
|
|
u16 cat;
|
|
int cat_prev = -1;
|
|
u32 iter;
|
|
|
|
if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01)
|
|
return -EFAULT;
|
|
|
|
for (iter = 0; iter < enumcat_len; iter += 2) {
|
|
cat = get_unaligned_be16(&enumcat[iter]);
|
|
if (cat <= cat_prev)
|
|
return -EFAULT;
|
|
cat_prev = cat;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network
|
|
* @doi_def: the DOI definition
|
|
* @secattr: the security attributes
|
|
* @net_cat: the zero'd out category list in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO category list in bytes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a local MLS category bitmap to the
|
|
* correct CIPSO category list using the given DOI definition. Returns the
|
|
* size in bytes of the network category bitmap on success, negative values
|
|
* otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr,
|
|
unsigned char *net_cat,
|
|
u32 net_cat_len)
|
|
{
|
|
int cat = -1;
|
|
u32 cat_iter = 0;
|
|
|
|
for (;;) {
|
|
cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1);
|
|
if (cat < 0)
|
|
break;
|
|
if ((cat_iter + 2) > net_cat_len)
|
|
return -ENOSPC;
|
|
|
|
*((__be16 *)&net_cat[cat_iter]) = htons(cat);
|
|
cat_iter += 2;
|
|
}
|
|
|
|
return cat_iter;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host
|
|
* @doi_def: the DOI definition
|
|
* @net_cat: the category list in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO bitmap in bytes
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a CIPSO category list to the correct
|
|
* local MLS category bitmap using the given DOI definition. Returns zero on
|
|
* success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *net_cat,
|
|
u32 net_cat_len,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
u32 iter;
|
|
|
|
for (iter = 0; iter < net_cat_len; iter += 2) {
|
|
ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat,
|
|
get_unaligned_be16(&net_cat[iter]),
|
|
GFP_ATOMIC);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid
|
|
* @doi_def: the DOI definition
|
|
* @rngcat: category list
|
|
* @rngcat_len: length of the category list in bytes
|
|
*
|
|
* Description:
|
|
* Checks the given categories against the given DOI definition and returns a
|
|
* negative value if any of the categories do not have a valid mapping and a
|
|
* zero value if all of the categories are valid.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *rngcat,
|
|
u32 rngcat_len)
|
|
{
|
|
u16 cat_high;
|
|
u16 cat_low;
|
|
u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1;
|
|
u32 iter;
|
|
|
|
if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01)
|
|
return -EFAULT;
|
|
|
|
for (iter = 0; iter < rngcat_len; iter += 4) {
|
|
cat_high = get_unaligned_be16(&rngcat[iter]);
|
|
if ((iter + 4) <= rngcat_len)
|
|
cat_low = get_unaligned_be16(&rngcat[iter + 2]);
|
|
else
|
|
cat_low = 0;
|
|
|
|
if (cat_high > cat_prev)
|
|
return -EFAULT;
|
|
|
|
cat_prev = cat_low;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network
|
|
* @doi_def: the DOI definition
|
|
* @secattr: the security attributes
|
|
* @net_cat: the zero'd out category list in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO category list in bytes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a local MLS category bitmap to the
|
|
* correct CIPSO category list using the given DOI definition. Returns the
|
|
* size in bytes of the network category bitmap on success, negative values
|
|
* otherwise.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr,
|
|
unsigned char *net_cat,
|
|
u32 net_cat_len)
|
|
{
|
|
int iter = -1;
|
|
u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2];
|
|
u32 array_cnt = 0;
|
|
u32 cat_size = 0;
|
|
|
|
/* make sure we don't overflow the 'array[]' variable */
|
|
if (net_cat_len >
|
|
(CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN))
|
|
return -ENOSPC;
|
|
|
|
for (;;) {
|
|
iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1);
|
|
if (iter < 0)
|
|
break;
|
|
cat_size += (iter == 0 ? 0 : sizeof(u16));
|
|
if (cat_size > net_cat_len)
|
|
return -ENOSPC;
|
|
array[array_cnt++] = iter;
|
|
|
|
iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter);
|
|
if (iter < 0)
|
|
return -EFAULT;
|
|
cat_size += sizeof(u16);
|
|
if (cat_size > net_cat_len)
|
|
return -ENOSPC;
|
|
array[array_cnt++] = iter;
|
|
}
|
|
|
|
for (iter = 0; array_cnt > 0;) {
|
|
*((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]);
|
|
iter += 2;
|
|
array_cnt--;
|
|
if (array[array_cnt] != 0) {
|
|
*((__be16 *)&net_cat[iter]) = htons(array[array_cnt]);
|
|
iter += 2;
|
|
}
|
|
}
|
|
|
|
return cat_size;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host
|
|
* @doi_def: the DOI definition
|
|
* @net_cat: the category list in network/CIPSO format
|
|
* @net_cat_len: the length of the CIPSO bitmap in bytes
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Perform a label mapping to translate a CIPSO category list to the correct
|
|
* local MLS category bitmap using the given DOI definition. Returns zero on
|
|
* success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *net_cat,
|
|
u32 net_cat_len,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
u32 net_iter;
|
|
u16 cat_low;
|
|
u16 cat_high;
|
|
|
|
for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) {
|
|
cat_high = get_unaligned_be16(&net_cat[net_iter]);
|
|
if ((net_iter + 4) <= net_cat_len)
|
|
cat_low = get_unaligned_be16(&net_cat[net_iter + 2]);
|
|
else
|
|
cat_low = 0;
|
|
|
|
ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat,
|
|
cat_low,
|
|
cat_high,
|
|
GFP_ATOMIC);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Protocol Handling Functions
|
|
*/
|
|
|
|
/**
|
|
* 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->attr.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,
|
|
&buffer[4],
|
|
buffer_len - 4);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
/* This will send packets using the "optimized" format when
|
|
* possible 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] = CIPSO_V4_TAG_RBITMAP;
|
|
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->attr.mls.lvl = level;
|
|
secattr->flags |= NETLBL_SECATTR_MLS_LVL;
|
|
|
|
if (tag_len > 4) {
|
|
ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def,
|
|
&tag[4],
|
|
tag_len - 4,
|
|
secattr);
|
|
if (ret_val != 0) {
|
|
netlbl_catmap_free(secattr->attr.mls.cat);
|
|
return ret_val;
|
|
}
|
|
|
|
secattr->flags |= NETLBL_SECATTR_MLS_CAT;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2)
|
|
* @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 enumerated tag, tag type #2. Returns the
|
|
* size of the tag on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_gentag_enum(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))
|
|
return -EPERM;
|
|
|
|
ret_val = cipso_v4_map_lvl_hton(doi_def,
|
|
secattr->attr.mls.lvl,
|
|
&level);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
|
|
if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
|
|
ret_val = cipso_v4_map_cat_enum_hton(doi_def,
|
|
secattr,
|
|
&buffer[4],
|
|
buffer_len - 4);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
tag_len = 4 + ret_val;
|
|
} else
|
|
tag_len = 4;
|
|
|
|
buffer[0] = CIPSO_V4_TAG_ENUM;
|
|
buffer[1] = tag_len;
|
|
buffer[3] = level;
|
|
|
|
return tag_len;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag
|
|
* @doi_def: the DOI definition
|
|
* @tag: the CIPSO tag
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Parse a CIPSO enumerated tag (tag type #2) and return the security
|
|
* attributes in @secattr. Return zero on success, negatives values on
|
|
* failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_parsetag_enum(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->attr.mls.lvl = level;
|
|
secattr->flags |= NETLBL_SECATTR_MLS_LVL;
|
|
|
|
if (tag_len > 4) {
|
|
ret_val = cipso_v4_map_cat_enum_ntoh(doi_def,
|
|
&tag[4],
|
|
tag_len - 4,
|
|
secattr);
|
|
if (ret_val != 0) {
|
|
netlbl_catmap_free(secattr->attr.mls.cat);
|
|
return ret_val;
|
|
}
|
|
|
|
secattr->flags |= NETLBL_SECATTR_MLS_CAT;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5)
|
|
* @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 ranged tag, tag type #5. Returns the
|
|
* size of the tag on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_gentag_rng(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))
|
|
return -EPERM;
|
|
|
|
ret_val = cipso_v4_map_lvl_hton(doi_def,
|
|
secattr->attr.mls.lvl,
|
|
&level);
|
|
if (ret_val != 0)
|
|
return ret_val;
|
|
|
|
if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
|
|
ret_val = cipso_v4_map_cat_rng_hton(doi_def,
|
|
secattr,
|
|
&buffer[4],
|
|
buffer_len - 4);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
tag_len = 4 + ret_val;
|
|
} else
|
|
tag_len = 4;
|
|
|
|
buffer[0] = CIPSO_V4_TAG_RANGE;
|
|
buffer[1] = tag_len;
|
|
buffer[3] = level;
|
|
|
|
return tag_len;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_parsetag_rng - Parse a CIPSO ranged tag
|
|
* @doi_def: the DOI definition
|
|
* @tag: the CIPSO tag
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Parse a CIPSO ranged tag (tag type #5) and return the security attributes
|
|
* in @secattr. Return zero on success, negatives values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_parsetag_rng(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->attr.mls.lvl = level;
|
|
secattr->flags |= NETLBL_SECATTR_MLS_LVL;
|
|
|
|
if (tag_len > 4) {
|
|
ret_val = cipso_v4_map_cat_rng_ntoh(doi_def,
|
|
&tag[4],
|
|
tag_len - 4,
|
|
secattr);
|
|
if (ret_val != 0) {
|
|
netlbl_catmap_free(secattr->attr.mls.cat);
|
|
return ret_val;
|
|
}
|
|
|
|
secattr->flags |= NETLBL_SECATTR_MLS_CAT;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard)
|
|
* @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 local tag. Returns the size of the tag
|
|
* on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr,
|
|
unsigned char *buffer,
|
|
u32 buffer_len)
|
|
{
|
|
if (!(secattr->flags & NETLBL_SECATTR_SECID))
|
|
return -EPERM;
|
|
|
|
buffer[0] = CIPSO_V4_TAG_LOCAL;
|
|
buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
|
|
*(u32 *)&buffer[2] = secattr->attr.secid;
|
|
|
|
return CIPSO_V4_TAG_LOC_BLEN;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_parsetag_loc - Parse a CIPSO local tag
|
|
* @doi_def: the DOI definition
|
|
* @tag: the CIPSO tag
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Parse a CIPSO local tag and return the security attributes in @secattr.
|
|
* Return zero on success, negatives values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
|
|
const unsigned char *tag,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
secattr->attr.secid = *(u32 *)&tag[2];
|
|
secattr->flags |= NETLBL_SECATTR_SECID;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_optptr - Find the CIPSO option in the packet
|
|
* @skb: the packet
|
|
*
|
|
* Description:
|
|
* Parse the packet's IP header looking for a CIPSO option. Returns a pointer
|
|
* to the start of the CIPSO option on success, NULL if one is not found.
|
|
*
|
|
*/
|
|
unsigned char *cipso_v4_optptr(const struct sk_buff *skb)
|
|
{
|
|
const struct iphdr *iph = ip_hdr(skb);
|
|
unsigned char *optptr = (unsigned char *)&(ip_hdr(skb)[1]);
|
|
int optlen;
|
|
int taglen;
|
|
|
|
for (optlen = iph->ihl*4 - sizeof(struct iphdr); optlen > 1; ) {
|
|
switch (optptr[0]) {
|
|
case IPOPT_END:
|
|
return NULL;
|
|
case IPOPT_NOOP:
|
|
taglen = 1;
|
|
break;
|
|
default:
|
|
taglen = optptr[1];
|
|
}
|
|
if (!taglen || taglen > optlen)
|
|
return NULL;
|
|
if (optptr[0] == IPOPT_CIPSO)
|
|
return optptr;
|
|
|
|
optlen -= taglen;
|
|
optptr += taglen;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* 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(const struct sk_buff *skb, 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(get_unaligned_be32(&opt[2]));
|
|
if (!doi_def) {
|
|
err_offset = 2;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
opt_iter = CIPSO_V4_HDR_LEN;
|
|
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;
|
|
}
|
|
|
|
if (opt_iter + 1 == opt_len) {
|
|
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 < CIPSO_V4_TAG_RBM_BLEN) {
|
|
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 > CIPSO_V4_TAG_RBM_BLEN &&
|
|
cipso_v4_map_cat_rbm_valid(doi_def,
|
|
&tag[4],
|
|
tag_len - 4) < 0) {
|
|
err_offset = opt_iter + 4;
|
|
goto validate_return_locked;
|
|
}
|
|
}
|
|
break;
|
|
case CIPSO_V4_TAG_ENUM:
|
|
if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) {
|
|
err_offset = opt_iter + 1;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
if (cipso_v4_map_lvl_valid(doi_def,
|
|
tag[3]) < 0) {
|
|
err_offset = opt_iter + 3;
|
|
goto validate_return_locked;
|
|
}
|
|
if (tag_len > CIPSO_V4_TAG_ENUM_BLEN &&
|
|
cipso_v4_map_cat_enum_valid(doi_def,
|
|
&tag[4],
|
|
tag_len - 4) < 0) {
|
|
err_offset = opt_iter + 4;
|
|
goto validate_return_locked;
|
|
}
|
|
break;
|
|
case CIPSO_V4_TAG_RANGE:
|
|
if (tag_len < CIPSO_V4_TAG_RNG_BLEN) {
|
|
err_offset = opt_iter + 1;
|
|
goto validate_return_locked;
|
|
}
|
|
|
|
if (cipso_v4_map_lvl_valid(doi_def,
|
|
tag[3]) < 0) {
|
|
err_offset = opt_iter + 3;
|
|
goto validate_return_locked;
|
|
}
|
|
if (tag_len > CIPSO_V4_TAG_RNG_BLEN &&
|
|
cipso_v4_map_cat_rng_valid(doi_def,
|
|
&tag[4],
|
|
tag_len - 4) < 0) {
|
|
err_offset = opt_iter + 4;
|
|
goto validate_return_locked;
|
|
}
|
|
break;
|
|
case CIPSO_V4_TAG_LOCAL:
|
|
/* This is a non-standard tag that we only allow for
|
|
* local connections, so if the incoming interface is
|
|
* not the loopback device drop the packet. Further,
|
|
* there is no legitimate reason for setting this from
|
|
* userspace so reject it if skb is NULL. */
|
|
if (!skb || !(skb->dev->flags & IFF_LOOPBACK)) {
|
|
err_offset = opt_iter;
|
|
goto validate_return_locked;
|
|
}
|
|
if (tag_len != CIPSO_V4_TAG_LOC_BLEN) {
|
|
err_offset = opt_iter + 1;
|
|
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 response 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 (ip_hdr(skb)->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_genopt - Generate a CIPSO option
|
|
* @buf: the option buffer
|
|
* @buf_len: the size of opt_buf
|
|
* @doi_def: the CIPSO DOI to use
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Generate a CIPSO option using the DOI definition and security attributes
|
|
* passed to the function. Returns the length of the option on success and
|
|
* negative values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
|
|
const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
u32 iter;
|
|
|
|
if (buf_len <= CIPSO_V4_HDR_LEN)
|
|
return -ENOSPC;
|
|
|
|
/* 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;
|
|
case CIPSO_V4_TAG_ENUM:
|
|
ret_val = cipso_v4_gentag_enum(doi_def,
|
|
secattr,
|
|
&buf[CIPSO_V4_HDR_LEN],
|
|
buf_len - CIPSO_V4_HDR_LEN);
|
|
break;
|
|
case CIPSO_V4_TAG_RANGE:
|
|
ret_val = cipso_v4_gentag_rng(doi_def,
|
|
secattr,
|
|
&buf[CIPSO_V4_HDR_LEN],
|
|
buf_len - CIPSO_V4_HDR_LEN);
|
|
break;
|
|
case CIPSO_V4_TAG_LOCAL:
|
|
ret_val = cipso_v4_gentag_loc(doi_def,
|
|
secattr,
|
|
&buf[CIPSO_V4_HDR_LEN],
|
|
buf_len - CIPSO_V4_HDR_LEN);
|
|
break;
|
|
default:
|
|
return -EPERM;
|
|
}
|
|
|
|
iter++;
|
|
} while (ret_val < 0 &&
|
|
iter < CIPSO_V4_TAG_MAXCNT &&
|
|
doi_def->tags[iter] != CIPSO_V4_TAG_INVALID);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
cipso_v4_gentag_hdr(doi_def, buf, ret_val);
|
|
return CIPSO_V4_HDR_LEN + ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_sock_setattr - Add a CIPSO option to a socket
|
|
* @sk: 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 @sk, which means it either needs to be in the
|
|
* process of being created or locked. Returns zero on success and negative
|
|
* values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_sock_setattr(struct sock *sk,
|
|
const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -EPERM;
|
|
unsigned char *buf = NULL;
|
|
u32 buf_len;
|
|
u32 opt_len;
|
|
struct ip_options_rcu *old, *opt = NULL;
|
|
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(). */
|
|
if (!sk)
|
|
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) {
|
|
ret_val = -ENOMEM;
|
|
goto socket_setattr_failure;
|
|
}
|
|
|
|
ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
|
|
if (ret_val < 0)
|
|
goto socket_setattr_failure;
|
|
buf_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) {
|
|
ret_val = -ENOMEM;
|
|
goto socket_setattr_failure;
|
|
}
|
|
memcpy(opt->opt.__data, buf, buf_len);
|
|
opt->opt.optlen = opt_len;
|
|
opt->opt.cipso = sizeof(struct iphdr);
|
|
kfree(buf);
|
|
buf = NULL;
|
|
|
|
sk_inet = inet_sk(sk);
|
|
|
|
old = rcu_dereference_protected(sk_inet->inet_opt,
|
|
lockdep_sock_is_held(sk));
|
|
if (sk_inet->is_icsk) {
|
|
sk_conn = inet_csk(sk);
|
|
if (old)
|
|
sk_conn->icsk_ext_hdr_len -= old->opt.optlen;
|
|
sk_conn->icsk_ext_hdr_len += opt->opt.optlen;
|
|
sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
|
|
}
|
|
rcu_assign_pointer(sk_inet->inet_opt, opt);
|
|
if (old)
|
|
kfree_rcu(old, rcu);
|
|
|
|
return 0;
|
|
|
|
socket_setattr_failure:
|
|
kfree(buf);
|
|
kfree(opt);
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_req_setattr - Add a CIPSO option to a connection request socket
|
|
* @req: the connection request 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. Returns zero on success and
|
|
* negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_req_setattr(struct request_sock *req,
|
|
const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -EPERM;
|
|
unsigned char *buf = NULL;
|
|
u32 buf_len;
|
|
u32 opt_len;
|
|
struct ip_options_rcu *opt = NULL;
|
|
struct inet_request_sock *req_inet;
|
|
|
|
/* 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) {
|
|
ret_val = -ENOMEM;
|
|
goto req_setattr_failure;
|
|
}
|
|
|
|
ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
|
|
if (ret_val < 0)
|
|
goto req_setattr_failure;
|
|
buf_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) {
|
|
ret_val = -ENOMEM;
|
|
goto req_setattr_failure;
|
|
}
|
|
memcpy(opt->opt.__data, buf, buf_len);
|
|
opt->opt.optlen = opt_len;
|
|
opt->opt.cipso = sizeof(struct iphdr);
|
|
kfree(buf);
|
|
buf = NULL;
|
|
|
|
req_inet = inet_rsk(req);
|
|
opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt);
|
|
if (opt)
|
|
kfree_rcu(opt, rcu);
|
|
|
|
return 0;
|
|
|
|
req_setattr_failure:
|
|
kfree(buf);
|
|
kfree(opt);
|
|
return ret_val;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_delopt - Delete the CIPSO option from a set of IP options
|
|
* @opt_ptr: IP option pointer
|
|
*
|
|
* Description:
|
|
* Deletes the CIPSO IP option from a set of IP options and makes the necessary
|
|
* adjustments to the IP option structure. Returns zero on success, negative
|
|
* values on failure.
|
|
*
|
|
*/
|
|
static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr)
|
|
{
|
|
struct ip_options_rcu *opt = rcu_dereference_protected(*opt_ptr, 1);
|
|
int hdr_delta = 0;
|
|
|
|
if (!opt || opt->opt.cipso == 0)
|
|
return 0;
|
|
if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) {
|
|
u8 cipso_len;
|
|
u8 cipso_off;
|
|
unsigned char *cipso_ptr;
|
|
int iter;
|
|
int optlen_new;
|
|
|
|
cipso_off = opt->opt.cipso - sizeof(struct iphdr);
|
|
cipso_ptr = &opt->opt.__data[cipso_off];
|
|
cipso_len = cipso_ptr[1];
|
|
|
|
if (opt->opt.srr > opt->opt.cipso)
|
|
opt->opt.srr -= cipso_len;
|
|
if (opt->opt.rr > opt->opt.cipso)
|
|
opt->opt.rr -= cipso_len;
|
|
if (opt->opt.ts > opt->opt.cipso)
|
|
opt->opt.ts -= cipso_len;
|
|
if (opt->opt.router_alert > opt->opt.cipso)
|
|
opt->opt.router_alert -= cipso_len;
|
|
opt->opt.cipso = 0;
|
|
|
|
memmove(cipso_ptr, cipso_ptr + cipso_len,
|
|
opt->opt.optlen - cipso_off - cipso_len);
|
|
|
|
/* determining the new total option length is tricky because of
|
|
* the padding necessary, the only thing i can think to do at
|
|
* this point is walk the options one-by-one, skipping the
|
|
* padding at the end to determine the actual option size and
|
|
* from there we can determine the new total option length */
|
|
iter = 0;
|
|
optlen_new = 0;
|
|
while (iter < opt->opt.optlen)
|
|
if (opt->opt.__data[iter] != IPOPT_NOP) {
|
|
iter += opt->opt.__data[iter + 1];
|
|
optlen_new = iter;
|
|
} else
|
|
iter++;
|
|
hdr_delta = opt->opt.optlen;
|
|
opt->opt.optlen = (optlen_new + 3) & ~3;
|
|
hdr_delta -= opt->opt.optlen;
|
|
} else {
|
|
/* only the cipso option was present on the socket so we can
|
|
* remove the entire option struct */
|
|
*opt_ptr = NULL;
|
|
hdr_delta = opt->opt.optlen;
|
|
kfree_rcu(opt, rcu);
|
|
}
|
|
|
|
return hdr_delta;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_sock_delattr - Delete the CIPSO option from a socket
|
|
* @sk: the socket
|
|
*
|
|
* Description:
|
|
* Removes the CIPSO option from a socket, if present.
|
|
*
|
|
*/
|
|
void cipso_v4_sock_delattr(struct sock *sk)
|
|
{
|
|
struct inet_sock *sk_inet;
|
|
int hdr_delta;
|
|
|
|
sk_inet = inet_sk(sk);
|
|
|
|
hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
|
|
if (sk_inet->is_icsk && hdr_delta > 0) {
|
|
struct inet_connection_sock *sk_conn = inet_csk(sk);
|
|
sk_conn->icsk_ext_hdr_len -= hdr_delta;
|
|
sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_req_delattr - Delete the CIPSO option from a request socket
|
|
* @reg: the request socket
|
|
*
|
|
* Description:
|
|
* Removes the CIPSO option from a request socket, if present.
|
|
*
|
|
*/
|
|
void cipso_v4_req_delattr(struct request_sock *req)
|
|
{
|
|
cipso_v4_delopt(&inet_rsk(req)->ireq_opt);
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
|
|
* @cipso: the CIPSO v4 option
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Inspect @cipso and return the security attributes in @secattr. Returns zero
|
|
* on success and negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_getattr(const unsigned char *cipso,
|
|
struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val = -ENOMSG;
|
|
u32 doi;
|
|
struct cipso_v4_doi *doi_def;
|
|
|
|
if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0)
|
|
return 0;
|
|
|
|
doi = get_unaligned_be32(&cipso[2]);
|
|
rcu_read_lock();
|
|
doi_def = cipso_v4_doi_search(doi);
|
|
if (!doi_def)
|
|
goto 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[6]) {
|
|
case CIPSO_V4_TAG_RBITMAP:
|
|
ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr);
|
|
break;
|
|
case CIPSO_V4_TAG_ENUM:
|
|
ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr);
|
|
break;
|
|
case CIPSO_V4_TAG_RANGE:
|
|
ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr);
|
|
break;
|
|
case CIPSO_V4_TAG_LOCAL:
|
|
ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr);
|
|
break;
|
|
}
|
|
if (ret_val == 0)
|
|
secattr->type = NETLBL_NLTYPE_CIPSOV4;
|
|
|
|
getattr_return:
|
|
rcu_read_unlock();
|
|
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)
|
|
{
|
|
struct ip_options_rcu *opt;
|
|
int res = -ENOMSG;
|
|
|
|
rcu_read_lock();
|
|
opt = rcu_dereference(inet_sk(sk)->inet_opt);
|
|
if (opt && opt->opt.cipso)
|
|
res = cipso_v4_getattr(opt->opt.__data +
|
|
opt->opt.cipso -
|
|
sizeof(struct iphdr),
|
|
secattr);
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_skbuff_setattr - Set the CIPSO option on a packet
|
|
* @skb: the packet
|
|
* @secattr: the security attributes
|
|
*
|
|
* Description:
|
|
* Set the CIPSO option on the given packet based on the security attributes.
|
|
* Returns a pointer to the IP header on success and NULL on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_skbuff_setattr(struct sk_buff *skb,
|
|
const struct cipso_v4_doi *doi_def,
|
|
const struct netlbl_lsm_secattr *secattr)
|
|
{
|
|
int ret_val;
|
|
struct iphdr *iph;
|
|
struct ip_options *opt = &IPCB(skb)->opt;
|
|
unsigned char buf[CIPSO_V4_OPT_LEN_MAX];
|
|
u32 buf_len = CIPSO_V4_OPT_LEN_MAX;
|
|
u32 opt_len;
|
|
int len_delta;
|
|
|
|
ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
buf_len = ret_val;
|
|
opt_len = (buf_len + 3) & ~3;
|
|
|
|
/* we overwrite any existing options to ensure that we have enough
|
|
* room for the CIPSO option, the reason is that we _need_ to guarantee
|
|
* that the security label is applied to the packet - we do the same
|
|
* thing when using the socket options and it hasn't caused a problem,
|
|
* if we need to we can always revisit this choice later */
|
|
|
|
len_delta = opt_len - opt->optlen;
|
|
/* if we don't ensure enough headroom we could panic on the skb_push()
|
|
* call below so make sure we have enough, we are also "mangling" the
|
|
* packet so we should probably do a copy-on-write call anyway */
|
|
ret_val = skb_cow(skb, skb_headroom(skb) + len_delta);
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
if (len_delta > 0) {
|
|
/* we assume that the header + opt->optlen have already been
|
|
* "pushed" in ip_options_build() or similar */
|
|
iph = ip_hdr(skb);
|
|
skb_push(skb, len_delta);
|
|
memmove((char *)iph - len_delta, iph, iph->ihl << 2);
|
|
skb_reset_network_header(skb);
|
|
iph = ip_hdr(skb);
|
|
} else if (len_delta < 0) {
|
|
iph = ip_hdr(skb);
|
|
memset(iph + 1, IPOPT_NOP, opt->optlen);
|
|
} else
|
|
iph = ip_hdr(skb);
|
|
|
|
if (opt->optlen > 0)
|
|
memset(opt, 0, sizeof(*opt));
|
|
opt->optlen = opt_len;
|
|
opt->cipso = sizeof(struct iphdr);
|
|
opt->is_changed = 1;
|
|
|
|
/* we have to do the following because we are being called from a
|
|
* netfilter hook which means the packet already has had the header
|
|
* fields populated and the checksum calculated - yes this means we
|
|
* are doing more work than needed but we do it to keep the core
|
|
* stack clean and tidy */
|
|
memcpy(iph + 1, buf, buf_len);
|
|
if (opt_len > buf_len)
|
|
memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len);
|
|
if (len_delta != 0) {
|
|
iph->ihl = 5 + (opt_len >> 2);
|
|
iph->tot_len = htons(skb->len);
|
|
}
|
|
ip_send_check(iph);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet
|
|
* @skb: the packet
|
|
*
|
|
* Description:
|
|
* Removes any and all CIPSO options from the given packet. Returns zero on
|
|
* success, negative values on failure.
|
|
*
|
|
*/
|
|
int cipso_v4_skbuff_delattr(struct sk_buff *skb)
|
|
{
|
|
int ret_val;
|
|
struct iphdr *iph;
|
|
struct ip_options *opt = &IPCB(skb)->opt;
|
|
unsigned char *cipso_ptr;
|
|
|
|
if (opt->cipso == 0)
|
|
return 0;
|
|
|
|
/* since we are changing the packet we should make a copy */
|
|
ret_val = skb_cow(skb, skb_headroom(skb));
|
|
if (ret_val < 0)
|
|
return ret_val;
|
|
|
|
/* the easiest thing to do is just replace the cipso option with noop
|
|
* options since we don't change the size of the packet, although we
|
|
* still need to recalculate the checksum */
|
|
|
|
iph = ip_hdr(skb);
|
|
cipso_ptr = (unsigned char *)iph + opt->cipso;
|
|
memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]);
|
|
opt->cipso = 0;
|
|
opt->is_changed = 1;
|
|
|
|
ip_send_check(iph);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Setup Functions
|
|
*/
|
|
|
|
/**
|
|
* cipso_v4_init - Initialize the CIPSO module
|
|
*
|
|
* 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);
|