nf_conntrack.h
/*
* Connection state tracking for netfilter. This is separated from,
* but required by, the (future) NAT layer; it can also be used by an iptables
* extension.
*
* 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
* - generalize L3 protocol dependent part.
*
* Derived from include/linux/netfiter_ipv4/ip_conntrack.h
*/
#ifndef _NF_CONNTRACK_H
#define _NF_CONNTRACK_H
#include <linux/netfilter/nf_conntrack_common.h>
#ifdef __KERNEL__
#include <linux/bitops.h>
#include <linux/compiler.h>
#include <asm/atomic.h>
#include <linux/netfilter/nf_conntrack_tcp.h>
#include <linux/netfilter/nf_conntrack_dccp.h>
#include <linux/netfilter/nf_conntrack_sctp.h>
#include <linux/netfilter/nf_conntrack_proto_gre.h>
#include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
#include <net/netfilter/nf_conntrack_tuple.h>
/* per conntrack: protocol private data */
union nf_conntrack_proto {
/* insert conntrack proto private data here */
struct nf_ct_dccp dccp;
struct ip_ct_sctp sctp;
struct ip_ct_tcp tcp;
struct nf_ct_gre gre;
};
union nf_conntrack_expect_proto {
/* insert expect proto private data here */
};
/* Add protocol helper include file here */
#include <linux/netfilter/nf_conntrack_ftp.h>
#include <linux/netfilter/nf_conntrack_pptp.h>
#include <linux/netfilter/nf_conntrack_h323.h>
#include <linux/netfilter/nf_conntrack_sane.h>
#include <linux/netfilter/nf_conntrack_sip.h>
/* per conntrack: application helper private data */
union nf_conntrack_help {
/* insert conntrack helper private data (master) here */
struct nf_ct_ftp_master ct_ftp_info;
struct nf_ct_pptp_master ct_pptp_info;
struct nf_ct_h323_master ct_h323_info;
struct nf_ct_sane_master ct_sane_info;
struct nf_ct_sip_master ct_sip_info;
};
#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/timer.h>
#ifdef CONFIG_NETFILTER_DEBUG
#define NF_CT_ASSERT(x) WARN_ON(!(x))
#else
#define NF_CT_ASSERT(x)
#endif
struct nf_conntrack_helper;
/* Must be kept in sync with the classes defined by helpers */
#define NF_CT_MAX_EXPECT_CLASSES 3
/* nf_conn feature for connections that have a helper */
struct nf_conn_help {
/* Helper. if any */
struct nf_conntrack_helper *helper;
union nf_conntrack_help help;
struct hlist_head expectations;
/* Current number of expected connections */
u8 expecting[NF_CT_MAX_EXPECT_CLASSES];
};
#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
struct nf_conn {
/* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
plus 1 for any connection(s) we are `master' for */
struct nf_conntrack ct_general;
spinlock_t lock;
/* XXX should I move this to the tail ? - Y.K */
/* These are my tuples; original and reply */
struct nf_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
/* Have we seen traffic both ways yet? (bitset) */
unsigned long status;
/* If we were expected by an expectation, this will be it */
struct nf_conn *master;
/* Timer function; drops refcnt when it goes off. */
struct timer_list timeout;
#if defined(CONFIG_NF_CONNTRACK_MARK)
u_int32_t mark;
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
u_int32_t secmark;
#endif
/* Storage reserved for other modules: */
union nf_conntrack_proto proto;
/* Extensions */
struct nf_ct_ext *ext;
#ifdef CONFIG_NET_NS
struct net *ct_net;
#endif
};
static inline struct nf_conn *
nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash *hash)
{
return container_of(hash, struct nf_conn,
tuplehash[hash->tuple.dst.dir]);
}
static inline u_int16_t nf_ct_l3num(const struct nf_conn *ct)
{
return ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
}
static inline u_int8_t nf_ct_protonum(const struct nf_conn *ct)
{
return ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
}
#define nf_ct_tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
/* get master conntrack via master expectation */
#define master_ct(conntr) (conntr->master)
extern struct net init_net;
static inline struct net *nf_ct_net(const struct nf_conn *ct)
{
#ifdef CONFIG_NET_NS
return ct->ct_net;
#else
return &init_net;
#endif
}
/* Alter reply tuple (maybe alter helper). */
extern void
nf_conntrack_alter_reply(struct nf_conn *ct,
const struct nf_conntrack_tuple *newreply);
/* Is this tuple taken? (ignoring any belonging to the given
conntrack). */
extern int
nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
const struct nf_conn *ignored_conntrack);
/* Return conntrack_info and tuple hash for given skb. */
static inline struct nf_conn *
nf_ct_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
{
*ctinfo = skb->nfctinfo;
return (struct nf_conn *)skb->nfct;
}
/* decrement reference count on a conntrack */
static inline void nf_ct_put(struct nf_conn *ct)
{
NF_CT_ASSERT(ct);
nf_conntrack_put(&ct->ct_general);
}
/* Protocol module loading */
extern int nf_ct_l3proto_try_module_get(unsigned short l3proto);
extern void nf_ct_l3proto_module_put(unsigned short l3proto);
/*
* Allocate a hashtable of hlist_head (if nulls == 0),
* or hlist_nulls_head (if nulls == 1)
*/
extern void *nf_ct_alloc_hashtable(unsigned int *sizep, int *vmalloced, int nulls);
extern void nf_ct_free_hashtable(void *hash, int vmalloced, unsigned int size);
extern struct nf_conntrack_tuple_hash *
__nf_conntrack_find(struct net *net, const struct nf_conntrack_tuple *tuple);
extern void nf_conntrack_hash_insert(struct nf_conn *ct);
extern void nf_ct_delete_from_lists(struct nf_conn *ct);
extern void nf_ct_insert_dying_list(struct nf_conn *ct);
extern void nf_conntrack_flush_report(struct net *net, u32 pid, int report);
extern bool nf_ct_get_tuplepr(const struct sk_buff *skb,
unsigned int nhoff, u_int16_t l3num,
struct nf_conntrack_tuple *tuple);
extern bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
const struct nf_conntrack_tuple *orig);
extern void __nf_ct_refresh_acct(struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
const struct sk_buff *skb,
unsigned long extra_jiffies,
int do_acct);
/* Refresh conntrack for this many jiffies and do accounting */
static inline void nf_ct_refresh_acct(struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
const struct sk_buff *skb,
unsigned long extra_jiffies)
{
__nf_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies, 1);
}
/* Refresh conntrack for this many jiffies */
static inline void nf_ct_refresh(struct nf_conn *ct,
const struct sk_buff *skb,
unsigned long extra_jiffies)
{
__nf_ct_refresh_acct(ct, 0, skb, extra_jiffies, 0);
}
extern bool __nf_ct_kill_acct(struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
const struct sk_buff *skb,
int do_acct);
/* kill conntrack and do accounting */
static inline bool nf_ct_kill_acct(struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
const struct sk_buff *skb)
{
return __nf_ct_kill_acct(ct, ctinfo, skb, 1);
}
/* kill conntrack without accounting */
static inline bool nf_ct_kill(struct nf_conn *ct)
{
return __nf_ct_kill_acct(ct, 0, NULL, 0);
}
/* These are for NAT. Icky. */
extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct,
enum ip_conntrack_dir dir,
u32 seq);
/* Fake conntrack entry for untracked connections */
extern struct nf_conn nf_conntrack_untracked;
/* Iterate over all conntracks: if iter returns true, it's deleted. */
extern void
nf_ct_iterate_cleanup(struct net *net, int (*iter)(struct nf_conn *i, void *data), void *data);
extern void nf_conntrack_free(struct nf_conn *ct);
extern struct nf_conn *
nf_conntrack_alloc(struct net *net,
const struct nf_conntrack_tuple *orig,
const struct nf_conntrack_tuple *repl,
gfp_t gfp);
/* It's confirmed if it is, or has been in the hash table. */
static inline int nf_ct_is_confirmed(struct nf_conn *ct)
{
return test_bit(IPS_CONFIRMED_BIT, &ct->status);
}
static inline int nf_ct_is_dying(struct nf_conn *ct)
{
return test_bit(IPS_DYING_BIT, &ct->status);
}
static inline int nf_ct_is_untracked(const struct sk_buff *skb)
{
return (skb->nfct == &nf_conntrack_untracked.ct_general);
}
extern int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp);
extern unsigned int nf_conntrack_htable_size;
extern unsigned int nf_conntrack_max;
#define NF_CT_STAT_INC(net, count) \
__this_cpu_inc((net)->ct.stat->count)
#define NF_CT_STAT_INC_ATOMIC(net, count) \
do { \
local_bh_disable(); \
__this_cpu_inc((net)->ct.stat->count); \
local_bh_enable(); \
} while (0)
#define MODULE_ALIAS_NFCT_HELPER(helper) \
MODULE_ALIAS("nfct-helper-" helper)
#endif /* __KERNEL__ */
#endif /* _NF_CONNTRACK_H */