path: root/net/ipv6/calipso.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * CALIPSO - Common Architecture Label IPv6 Security Option
 *
 * This is an implementation of the CALIPSO protocol as specified in
 * RFC 5570.
 *
 * Authors: Paul Moore <paul.moore@hp.com>
 *          Huw Davies <huw@codeweavers.com>
 */

/* (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008
 * (c) Copyright Huw Davies <huw@codeweavers.com>, 2015
 */

#include <linux/init.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/jhash.h>
#include <linux/audit.h>
#include <linux/slab.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/tcp.h>
#include <net/netlabel.h>
#include <net/calipso.h>
#include <linux/atomic.h>
#include <linux/bug.h>
#include <asm/unaligned.h>
#include <linux/crc-ccitt.h>

/* Maximium size of the calipso option including
 * the two-byte TLV header.
 */
#define CALIPSO_OPT_LEN_MAX (2 + 252)

/* Size of the minimum calipso option including
 * the two-byte TLV header.
 */
#define CALIPSO_HDR_LEN (2 + 8)

/* Maximium size of the calipso option including
 * the two-byte TLV header and upto 3 bytes of
 * leading pad and 7 bytes of trailing pad.
 */
#define CALIPSO_OPT_LEN_MAX_WITH_PAD (3 + CALIPSO_OPT_LEN_MAX + 7)

 /* Maximium size of u32 aligned buffer required to hold calipso
  * option.  Max of 3 initial pad bytes starting from buffer + 3.
  * i.e. the worst case is when the previous tlv finishes on 4n + 3.
  */
#define CALIPSO_MAX_BUFFER (6 + CALIPSO_OPT_LEN_MAX)

/* List of available DOI definitions */
static DEFINE_SPINLOCK(calipso_doi_list_lock);
static LIST_HEAD(calipso_doi_list);

/* Label mapping cache */
int calipso_cache_enabled = 1;
int calipso_cache_bucketsize = 10;
#define CALIPSO_CACHE_BUCKETBITS     7
#define CALIPSO_CACHE_BUCKETS        BIT(CALIPSO_CACHE_BUCKETBITS)
#define CALIPSO_CACHE_REORDERLIMIT   10
struct calipso_map_cache_bkt {
	spinlock_t lock;
	u32 size;
	struct list_head list;
};

struct calipso_map_cache_entry {
	u32 hash;
	unsigned char *key;
	size_t key_len;

	struct netlbl_lsm_cache *lsm_data;

	u32 activity