/* Connection state tracking for netfilter. This is separated from,
but required by, the NAT layer; it can also be used by an iptables
extension. */
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
* (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/types.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/vmalloc.h>
#include <linux/stddef.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/jhash.h>
#include <linux/err.h>
#include <linux/percpu.h>
#include <linux/moduleparam.h>
#include <linux/notifier.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/socket.h>
#include <linux/mm.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_extend.h>
#include <net/netfilter/nf_conntrack_acct.h>
#define NF_CONNTRACK_VERSION "0.5.0"
DEFINE_SPINLOCK(nf_conntrack_lock);
EXPORT_SYMBOL_GPL(nf_conntrack_lock);
/* nf_conntrack_standalone needs this */
atomic_t nf_conntrack_count = ATOMIC_INIT(0);
EXPORT_SYMBOL_GPL(nf_conntrack_count);
unsigned int nf_conntrack_htable_size __read_mostly;
EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
int nf_conntrack_max __read_mostly;
EXPORT_SYMBOL_GPL(nf_conntrack_max);
struct hlist_head *nf_conntrack_hash __read_mostly;
EXPORT_SYMBOL_GPL(nf_conntrack_hash);
struct nf_conn nf_conntrack_untracked __read_mostly;
EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
unsigned int nf_ct_log_invalid __read_mostly;
HLIST_HEAD(unconfirmed);
static int nf_conntrack_vmalloc __read_mostly;
static struct kmem_cache *nf_conntrack_cachep __read_mostly;
DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);
static int nf_conntrack_hash_rnd_initted;
static unsigned int nf_conntrack_hash_rnd;
static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
unsigned int size, unsigned int rnd)
{
unsigned int n;
u_int32_t h;
/* The direction must be ignored, so we hash everything up to the
* destination ports (which is a multiple of 4) and treat the last
* three bytes manually.
*/
n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32);
h = jhash2((u32 *)tuple, n,
rnd ^ (((__force __u16)tuple->dst.u.all << 16) |
tuple->dst.protonum));
return ((u64)h * size) >> 32;
}
static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
{
return __hash_conntrack(tuple, nf_conntrack_htable_size,
nf_conntrack_hash_rnd);
}
bool
nf_ct_get_tuple(const struct sk_buff *skb,
unsigned int nhoff,
unsigned int dataoff,
u_int16_t l3num,
u_int8_t protonum,
struct nf_conntrack_tuple *tuple,
const struct nf_conntrack_l3proto *l3proto,
const struct nf_conntrack_l4proto *l4proto)
{
memset(tuple, 0, sizeof(*tuple));
tuple->src.l3num = l3num;
if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0