[mirror_ubuntu-zesty-kernel.git] / include / linux / netfilter.h

#ifndef __LINUX_NETFILTER_H
#define __LINUX_NETFILTER_H

#ifdef __KERNEL__
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/net.h>
#include <linux/if.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/wait.h>
#include <linux/list.h>
#endif
#include <linux/types.h>
#include <linux/compiler.h>

/* Responses from hook functions. */
#define NF_DROP 0
#define NF_ACCEPT 1
#define NF_STOLEN 2
#define NF_QUEUE 3
#define NF_REPEAT 4
#define NF_STOP 5
#define NF_MAX_VERDICT NF_STOP

/* we overload the higher bits for encoding auxiliary data such as the queue
 * number or errno values. Not nice, but better than additional function
 * arguments. */
#define NF_VERDICT_MASK 0x000000ff

/* extra verdict flags have mask 0x0000ff00 */

/* queue number (NF_QUEUE) or errno (NF_DROP) */
#define NF_VERDICT_QMASK 0xffff0000
#define NF_VERDICT_QBITS 16

#define NF_QUEUE_NR(x) ((((x) << 16) & NF_VERDICT_QMASK) | NF_QUEUE)

#define NF_DROP_ERR(x) (((-x) << 16) | NF_DROP)

/* only for userspace compatibility */
#ifndef __KERNEL__
/* Generic cache responses from hook functions.
   <= 0x2000 is used for protocol-flags. */
#define NFC_UNKNOWN 0x4000
#define NFC_ALTERED 0x8000

/* NF_VERDICT_BITS should be 8 now, but userspace might break if this changes */
#define NF_VERDICT_BITS 16
#endif

enum nf_inet_hooks {
	NF_INET_PRE_ROUTING,
	NF_INET_LOCAL_IN,
	NF_INET_FORWARD,
	NF_INET_LOCAL_OUT,
	NF_INET_POST_ROUTING,
	NF_INET_NUMHOOKS
};

enum {
	NFPROTO_UNSPEC =  0,
	NFPROTO_IPV4   =  2,
	NFPROTO_ARP    =  3,
	NFPROTO_BRIDGE =  7,
	NFPROTO_IPV6   = 10,
	NFPROTO_DECNET = 12,
	NFPROTO_NUMPROTO,
};

union nf_inet_addr {
	__u32		all[4];
	__be32		ip;
	__be32		ip6[4];
	struct in_addr	in;
	struct in6_addr	in6;
};

#ifdef __KERNEL__
#ifdef CONFIG_NETFILTER
static inline int NF_DROP_GETERR(int verdict)
{
	return -(verdict >> NF_VERDICT_QBITS);
}

static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
				   const union nf_inet_addr *a2)
{
	return a1->all[0] == a2->all[0] &&
	       a1->all[1] == a2->all[1] &&
	       a1->all[2] == a2->all[2] &&
	       a1->all[3] == a2->all[3];
}

extern void netfilter_init(void);

/* Largest hook number + 1 */
#define NF_MAX_HOOKS 8

struct sk_buff;

typedef unsigned int nf_hookfn(unsigned int hooknum,
			       struct sk_buff *skb,
			       const struct net_device *in,
			       const struct net_device *out,
			       int (*okfn)(struct sk_buff *));

struct nf_hook_ops {
	struct list_head list;

	/* User fills in from here down. */
	nf_hookfn *hook;
	struct module *owner;
	u_int8_t pf;
	unsigned int hooknum;
	/* Hooks are ordered in ascending priority. */
	int priority;
};

struct nf_sockopt_ops {
	struct list_head list;

	u_int8_t pf;

	/* Non-inclusive ranges: use 0/0/NULL to never get called. */
	int set_optmin;
	int set_optmax;
	int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len);
#ifdef CONFIG_COMPAT
	int (*compat_set)(struct sock *sk, int optval,
			void __user *user, unsigned int len);
#endif
	int get_optmin;
	int get_optmax;
	int (*get)(struct sock *sk, int optval, void __user *user, int *len);
#ifdef CONFIG_COMPAT
	int (*compat_get)(struct sock *sk, int optval,
			void __user *user, int *len);
#endif
	/* Use the module struct to lock set/get code in place */
	struct module *owner;
};

/* Function to register/unregister hook points. */
int nf_register_hook(struct nf_hook_ops *reg);
void nf_unregister_hook(struct nf_hook_ops *reg);
int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);

/* Functions to register get/setsockopt ranges (non-inclusive).  You
   need to check permissions yourself! */
int nf_register_sockopt(struct nf_sockopt_ops *reg);
void nf_unregister_sockopt(struct nf_sockopt_ops *reg);

#ifdef CONFIG_SYSCTL
/* Sysctl registration */
extern struct ctl_path nf_net_netfilter_sysctl_path[];
extern struct ctl_path nf_net_ipv4_netfilter_sysctl_path[];
#endif /* CONFIG_SYSCTL */

extern struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS];

int nf_hook_slow(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
		 struct net_device *indev, struct net_device *outdev,
		 int (*okfn)(struct sk_buff *), int thresh);

/**
 *	nf_hook_thresh - call a netfilter hook
 *	
 *	Returns 1 if the hook has allowed the packet to pass.  The function
 *	okfn must be invoked by the caller in this case.  Any other return
 *	value indicates the packet has been consumed by the hook.
 */
static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
				 struct sk_buff *skb,
				 struct net_device *indev,
				 struct net_device *outdev,
				 int (*okfn)(struct sk_buff *), int thresh)
{
#ifndef CONFIG_NETFILTER_DEBUG
	if (list_empty(&nf_hooks[pf][hook]))
		return 1;
#endif
	return nf_hook_slow(pf, hook, skb, indev, outdev, okfn, thresh);
}

static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
			  struct net_device *indev, struct net_device *outdev,
			  int (*okfn)(struct sk_buff *))
{
	return nf_hook_thresh(pf, hook, skb, indev, outdev, okfn, INT_MIN);
}
                   
/* Activate hook; either okfn or kfree_skb called, unless a hook
   returns NF_STOLEN (in which case, it's up to the hook to deal with
   the consequences).

   Returns -ERRNO if packet dropped.  Zero means queued, stolen or
   accepted.
*/

/* RR:
   > I don't want nf_hook to return anything because people might forget
   > about async and trust the return value to mean "packet was ok".

   AK:
   Just document it clearly, then you can expect some sense from kernel
   coders :)
*/

static inline int
NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	       struct net_device *in, struct net_device *out,
	       int (*okfn)(struct sk_buff *), int thresh)
{
	int ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, thresh);
	if (ret == 1)
		ret = okfn(skb);
	return ret;
}

static inline int
NF_HOOK_COND(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	     struct net_device *in, struct net_device *out,
	     int (*okfn)(struct sk_buff *), bool cond)
{
	int ret;

	if (!cond ||
	    ((ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, INT_MIN)) == 1))
		ret = okfn(skb);
	return ret;
}

static inline int
NF_HOOK(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	struct net_device *in, struct net_device *out,
	int (*okfn)(struct sk_buff *))
{
	return NF_HOOK_THRESH(pf, hook, skb, in, out, okfn, INT_MIN);
}

/* Call setsockopt() */
int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
		  unsigned int len);
int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
		  int *len);
#ifdef CONFIG_COMPAT
int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
		char __user *opt, unsigned int len);
int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
		char __user *opt, int *len);
#endif

/* Call this before modifying an existing packet: ensures it is
   modifiable and linear to the point you care about (writable_len).
   Returns true or false. */
extern int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);

struct flowi;
struct nf_queue_entry;

struct nf_afinfo {
	unsigned short	family;
	__sum16		(*checksum)(struct sk_buff *skb, unsigned int hook,
				    unsigned int dataoff, u_int8_t protocol);
	__sum16		(*checksum_partial)(struct sk_buff *skb,
					    unsigned int hook,
					    unsigned int dataoff,
					    unsigned int len,
					    u_int8_t protocol);
	int		(*route)(struct dst_entry **dst, struct flowi *fl);
	void		(*saveroute)(const struct sk_buff *skb,
				     struct nf_queue_entry *entry);
	int		(*reroute)(struct sk_buff *skb,
				   const struct nf_queue_entry *entry);
	int		route_key_size;
};

extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
{
	return rcu_dereference(nf_afinfo[family]);
}

static inline __sum16
nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
	    u_int8_t protocol, unsigned short family)
{
	const struct nf_afinfo *afinfo;
	__sum16 csum = 0;

	rcu_read_lock();
	afinfo = nf_get_afinfo(family);
	if (afinfo)
		csum = afinfo->checksum(skb, hook, dataoff, protocol);
	rcu_read_unlock();
	return csum;
}

static inline __sum16
nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
		    unsigned int dataoff, unsigned int len,
		    u_int8_t protocol, unsigned short family)
{
	const struct nf_afinfo *afinfo;
	__sum16 csum = 0;

	rcu_read_lock();
	afinfo = nf_get_afinfo(family);
	if (afinfo)
		csum = afinfo->checksum_partial(skb, hook, dataoff, len,
						protocol);
	rcu_read_unlock();
	return csum;
}

extern int nf_register_afinfo(const struct nf_afinfo *afinfo);
extern void nf_unregister_afinfo(const struct nf_afinfo *afinfo);

#include <net/flow.h>
extern void (*ip_nat_decode_session)(struct sk_buff *, struct flowi *);

static inline void
nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
{
#ifdef CONFIG_NF_NAT_NEEDED
	void (*decodefn)(struct sk_buff *, struct flowi *);

	if (family == AF_INET) {
		rcu_read_lock();
		decodefn = rcu_dereference(ip_nat_decode_session);
		if (decodefn)
			decodefn(skb, fl);
		rcu_read_unlock();
	}
#endif
}

#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
extern struct proc_dir_entry *proc_net_netfilter;
#endif

#else /* !CONFIG_NETFILTER */
#define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb)
#define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) (okfn)(skb)
static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
				 struct sk_buff *skb,
				 struct net_device *indev,
				 struct net_device *outdev,
				 int (*okfn)(struct sk_buff *), int thresh)
{
	return okfn(skb);
}
static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
			  struct net_device *indev, struct net_device *outdev,
			  int (*okfn)(struct sk_buff *))
{
	return 1;
}
struct flowi;
static inline void
nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
{
}
#endif /*CONFIG_NETFILTER*/

#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
extern void (*ip_ct_attach)(struct sk_buff *, struct sk_buff *) __rcu;
extern void nf_ct_attach(struct sk_buff *, struct sk_buff *);
extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu;
#else
static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
#endif

#endif /*__KERNEL__*/
#endif /*__LINUX_NETFILTER_H*/
Commit	Line	Data
1da177e4 LT	1	#ifndef __LINUX_NETFILTER_H
	2	#define __LINUX_NETFILTER_H
	3
	4	#ifdef __KERNEL__
	5	#include <linux/init.h>
1da177e4 LT	6	#include <linux/skbuff.h>
	7	#include <linux/net.h>
	8	#include <linux/if.h>
2e3075a2 JE	9	#include <linux/in.h>
2e3075a2 JE	10	#include <linux/in6.h>
1da177e4 LT	11	#include <linux/wait.h>
	12	#include <linux/list.h>
	13	#endif
c8942f1f	14	#include <linux/types.h>
1da177e4 LT	15	#include <linux/compiler.h>
	16
	17	/* Responses from hook functions. */
	18	#define NF_DROP 0
	19	#define NF_ACCEPT 1
	20	#define NF_STOLEN 2
	21	#define NF_QUEUE 3
	22	#define NF_REPEAT 4
	23	#define NF_STOP 5
	24	#define NF_MAX_VERDICT NF_STOP
	25
0ab43f84	26	/* we overload the higher bits for encoding auxiliary data such as the queue
f615df76 FW	27	* number or errno values. Not nice, but better than additional function
	28	* arguments. */
	29	#define NF_VERDICT_MASK 0x000000ff
	30
	31	/* extra verdict flags have mask 0x0000ff00 */
0ab43f84	32
f615df76	33	/* queue number (NF_QUEUE) or errno (NF_DROP) */
0ab43f84 HW	34	#define NF_VERDICT_QMASK 0xffff0000
	35	#define NF_VERDICT_QBITS 16
	36
f615df76	37	#define NF_QUEUE_NR(x) ((((x) << 16) & NF_VERDICT_QMASK) \| NF_QUEUE)
0ab43f84	38
f615df76	39	#define NF_DROP_ERR(x) (((-x) << 16) \| NF_DROP)
da683650	40
6869c4d8 HW	41	/* only for userspace compatibility */
6869c4d8 HW	42	#ifndef __KERNEL__
1da177e4 LT	43	/* Generic cache responses from hook functions.
	44	<= 0x2000 is used for protocol-flags. */
	45	#define NFC_UNKNOWN 0x4000
	46	#define NFC_ALTERED 0x8000
f615df76 FW	47
	48	/* NF_VERDICT_BITS should be 8 now, but userspace might break if this changes */
	49	#define NF_VERDICT_BITS 16
6869c4d8	50	#endif
1da177e4	51
6e23ae2a PM	52	enum nf_inet_hooks {
	53	NF_INET_PRE_ROUTING,
	54	NF_INET_LOCAL_IN,
	55	NF_INET_FORWARD,
	56	NF_INET_LOCAL_OUT,
	57	NF_INET_POST_ROUTING,
	58	NF_INET_NUMHOOKS
	59	};
	60
7e9c6eeb JE	61	enum {
	62	NFPROTO_UNSPEC = 0,
	63	NFPROTO_IPV4 = 2,
	64	NFPROTO_ARP = 3,
	65	NFPROTO_BRIDGE = 7,
	66	NFPROTO_IPV6 = 10,
	67	NFPROTO_DECNET = 12,
	68	NFPROTO_NUMPROTO,
	69	};
	70
643a2c15	71	union nf_inet_addr {
7b33ed22	72	__u32 all[4];
643a2c15 JE	73	__be32 ip;
643a2c15 JE	74	__be32 ip6[4];
2e3075a2 JE	75	struct in_addr in;
2e3075a2 JE	76	struct in6_addr in6;
643a2c15 JE	77	};
643a2c15 JE	78
1da177e4	79	#ifdef __KERNEL__
1da177e4	80	#ifdef CONFIG_NETFILTER
f615df76 FW	81	static inline int NF_DROP_GETERR(int verdict)
	82	{
	83	return -(verdict >> NF_VERDICT_QBITS);
	84	}
1da177e4	85
b8beedd2 PM	86	static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
	87	const union nf_inet_addr *a2)
	88	{
	89	return a1->all[0] == a2->all[0] &&
	90	a1->all[1] == a2->all[1] &&
	91	a1->all[2] == a2->all[2] &&
	92	a1->all[3] == a2->all[3];
	93	}
	94
1da177e4 LT	95	extern void netfilter_init(void);
	96
	97	/* Largest hook number + 1 */
	98	#define NF_MAX_HOOKS 8
	99
	100	struct sk_buff;
1da177e4 LT	101
1da177e4 LT	102	typedef unsigned int nf_hookfn(unsigned int hooknum,
3db05fea	103	struct sk_buff *skb,
1da177e4 LT	104	const struct net_device *in,
	105	const struct net_device *out,
	106	int (okfn)(struct sk_buff ));
	107
d94d9fee	108	struct nf_hook_ops {
1da177e4 LT	109	struct list_head list;
	110
	111	/* User fills in from here down. */
	112	nf_hookfn *hook;
	113	struct module *owner;
76108cea JE	114	u_int8_t pf;
76108cea JE	115	unsigned int hooknum;
1da177e4 LT	116	/* Hooks are ordered in ascending priority. */
	117	int priority;
	118	};
	119
d94d9fee	120	struct nf_sockopt_ops {
1da177e4 LT	121	struct list_head list;
1da177e4 LT	122
76108cea	123	u_int8_t pf;
1da177e4 LT	124
	125	/* Non-inclusive ranges: use 0/0/NULL to never get called. */
	126	int set_optmin;
	127	int set_optmax;
	128	int (set)(struct sock sk, int optval, void __user *user, unsigned int len);
c30f540b	129	#ifdef CONFIG_COMPAT
3fdadf7d DM	130	int (compat_set)(struct sock sk, int optval,
3fdadf7d DM	131	void __user *user, unsigned int len);
c30f540b	132	#endif
1da177e4 LT	133	int get_optmin;
	134	int get_optmax;
	135	int (get)(struct sock sk, int optval, void __user user, int len);
c30f540b	136	#ifdef CONFIG_COMPAT
3fdadf7d DM	137	int (compat_get)(struct sock sk, int optval,
3fdadf7d DM	138	void __user user, int len);
c30f540b	139	#endif
16fcec35 NH	140	/* Use the module struct to lock set/get code in place */
16fcec35 NH	141	struct module *owner;
1da177e4 LT	142	};
1da177e4 LT	143
1da177e4 LT	144	/* Function to register/unregister hook points. */
	145	int nf_register_hook(struct nf_hook_ops *reg);
	146	void nf_unregister_hook(struct nf_hook_ops *reg);
972d1cb1 PM	147	int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
972d1cb1 PM	148	void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
1da177e4 LT	149
	150	/* Functions to register get/setsockopt ranges (non-inclusive). You
	151	need to check permissions yourself! */
	152	int nf_register_sockopt(struct nf_sockopt_ops *reg);
	153	void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
	154
d62f9ed4 PM	155	#ifdef CONFIG_SYSCTL
d62f9ed4 PM	156	/* Sysctl registration */
b3fd3ffe PE	157	extern struct ctl_path nf_net_netfilter_sysctl_path[];
b3fd3ffe PE	158	extern struct ctl_path nf_net_ipv4_netfilter_sysctl_path[];
d62f9ed4 PM	159	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	160
7e9c6eeb	161	extern struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
1da177e4	162
76108cea	163	int nf_hook_slow(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
16a6677f PM	164	struct net_device indev, struct net_device outdev,
	165	int (okfn)(struct sk_buff ), int thresh);
	166
	167	/**
	168	* nf_hook_thresh - call a netfilter hook
	169	*
	170	* Returns 1 if the hook has allowed the packet to pass. The function
	171	* okfn must be invoked by the caller in this case. Any other return
	172	* value indicates the packet has been consumed by the hook.
	173	*/
76108cea	174	static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
3db05fea	175	struct sk_buff *skb,
16a6677f PM	176	struct net_device *indev,
16a6677f PM	177	struct net_device *outdev,
23f3733d	178	int (okfn)(struct sk_buff ), int thresh)
16a6677f PM	179	{
	180	#ifndef CONFIG_NETFILTER_DEBUG
	181	if (list_empty(&nf_hooks[pf][hook]))
	182	return 1;
	183	#endif
3db05fea	184	return nf_hook_slow(pf, hook, skb, indev, outdev, okfn, thresh);
16a6677f PM	185	}
16a6677f PM	186
76108cea	187	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
16a6677f PM	188	struct net_device indev, struct net_device outdev,
	189	int (okfn)(struct sk_buff ))
	190	{
23f3733d	191	return nf_hook_thresh(pf, hook, skb, indev, outdev, okfn, INT_MIN);
16a6677f	192	}
1da177e4 LT	193
	194	/* Activate hook; either okfn or kfree_skb called, unless a hook
	195	returns NF_STOLEN (in which case, it's up to the hook to deal with
	196	the consequences).
	197
	198	Returns -ERRNO if packet dropped. Zero means queued, stolen or
	199	accepted.
	200	*/
	201
	202	/* RR:
	203	> I don't want nf_hook to return anything because people might forget
	204	> about async and trust the return value to mean "packet was ok".
	205
	206	AK:
	207	Just document it clearly, then you can expect some sense from kernel
	208	coders :)
	209	*/
	210
2249065f JE	211	static inline int
	212	NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	213	struct net_device in, struct net_device out,
	214	int (okfn)(struct sk_buff ), int thresh)
	215	{
	216	int ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, thresh);
	217	if (ret == 1)
	218	ret = okfn(skb);
	219	return ret;
	220	}
48d5cad8	221
2249065f JE	222	static inline int
	223	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	224	struct net_device in, struct net_device out,
	225	int (okfn)(struct sk_buff ), bool cond)
	226	{
4bac6b18 PM	227	int ret;
	228
	229	if (!cond \|\|
ac5aa2e3	230	((ret = nf_hook_thresh(pf, hook, skb, in, out, okfn, INT_MIN)) == 1))
2249065f JE	231	ret = okfn(skb);
	232	return ret;
	233	}
1da177e4	234
2249065f JE	235	static inline int
	236	NF_HOOK(uint8_t pf, unsigned int hook, struct sk_buff *skb,
	237	struct net_device in, struct net_device out,
	238	int (okfn)(struct sk_buff ))
	239	{
	240	return NF_HOOK_THRESH(pf, hook, skb, in, out, okfn, INT_MIN);
	241	}
1da177e4 LT	242
1da177e4 LT	243	/* Call setsockopt() */
76108cea	244	int nf_setsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
b7058842	245	unsigned int len);
76108cea	246	int nf_getsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
1da177e4	247	int *len);
c30f540b	248	#ifdef CONFIG_COMPAT
76108cea	249	int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
b7058842	250	char __user *opt, unsigned int len);
76108cea	251	int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
3fdadf7d	252	char __user opt, int len);
c30f540b	253	#endif
3fdadf7d	254
089af26c HW	255	/* Call this before modifying an existing packet: ensures it is
	256	modifiable and linear to the point you care about (writable_len).
	257	Returns true or false. */
37d41879	258	extern int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
089af26c	259
1841a4c7	260	struct flowi;
02f014d8	261	struct nf_queue_entry;
c01cd429	262
bce8032e PM	263	struct nf_afinfo {
bce8032e PM	264	unsigned short family;
b51655b9	265	__sum16 (checksum)(struct sk_buff skb, unsigned int hook,
422c346f	266	unsigned int dataoff, u_int8_t protocol);
d63a6507 PM	267	__sum16 (checksum_partial)(struct sk_buff skb,
	268	unsigned int hook,
	269	unsigned int dataoff,
	270	unsigned int len,
	271	u_int8_t protocol);
1841a4c7	272	int (route)(struct dst_entry dst, struct flowi fl);
bce8032e	273	void (saveroute)(const struct sk_buff skb,
02f014d8	274	struct nf_queue_entry *entry);
3db05fea	275	int (reroute)(struct sk_buff skb,
02f014d8	276	const struct nf_queue_entry *entry);
bce8032e	277	int route_key_size;
2cc7d573 HW	278	};
2cc7d573 HW	279
0e60ebe0	280	extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
1e796fda	281	static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
bce8032e PM	282	{
	283	return rcu_dereference(nf_afinfo[family]);
	284	}
2cc7d573	285
b51655b9	286	static inline __sum16
422c346f PM	287	nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
	288	u_int8_t protocol, unsigned short family)
	289	{
1e796fda	290	const struct nf_afinfo *afinfo;
b51655b9	291	__sum16 csum = 0;
422c346f PM	292
	293	rcu_read_lock();
	294	afinfo = nf_get_afinfo(family);
	295	if (afinfo)
	296	csum = afinfo->checksum(skb, hook, dataoff, protocol);
	297	rcu_read_unlock();
	298	return csum;
	299	}
	300
d63a6507 PM	301	static inline __sum16
	302	nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
	303	unsigned int dataoff, unsigned int len,
	304	u_int8_t protocol, unsigned short family)
	305	{
	306	const struct nf_afinfo *afinfo;
	307	__sum16 csum = 0;
	308
	309	rcu_read_lock();
	310	afinfo = nf_get_afinfo(family);
	311	if (afinfo)
	312	csum = afinfo->checksum_partial(skb, hook, dataoff, len,
	313	protocol);
	314	rcu_read_unlock();
	315	return csum;
	316	}
	317
1e796fda PM	318	extern int nf_register_afinfo(const struct nf_afinfo *afinfo);
1e796fda PM	319	extern void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
bce8032e	320
eb9c7ebe PM	321	#include <net/flow.h>
	322	extern void (ip_nat_decode_session)(struct sk_buff , struct flowi *);
	323
	324	static inline void
76108cea	325	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
eb9c7ebe	326	{
051578cc	327	#ifdef CONFIG_NF_NAT_NEEDED
eb9c7ebe PM	328	void (decodefn)(struct sk_buff , struct flowi *);
eb9c7ebe PM	329
051578cc PM	330	if (family == AF_INET) {
	331	rcu_read_lock();
	332	decodefn = rcu_dereference(ip_nat_decode_session);
	333	if (decodefn)
	334	decodefn(skb, fl);
	335	rcu_read_unlock();
	336	}
eb9c7ebe PM	337	#endif
	338	}
	339
608c8e4f HW	340	#ifdef CONFIG_PROC_FS
	341	#include <linux/proc_fs.h>
	342	extern struct proc_dir_entry *proc_net_netfilter;
	343	#endif
	344
1da177e4 LT	345	#else /* !CONFIG_NETFILTER */
1da177e4 LT	346	#define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb)
48d5cad8	347	#define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) (okfn)(skb)
76108cea	348	static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
3db05fea	349	struct sk_buff *skb,
f53b61d8 DM	350	struct net_device *indev,
f53b61d8 DM	351	struct net_device *outdev,
23f3733d	352	int (okfn)(struct sk_buff ), int thresh)
f53b61d8	353	{
3db05fea	354	return okfn(skb);
f53b61d8	355	}
76108cea	356	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
f53b61d8 DM	357	struct net_device indev, struct net_device outdev,
	358	int (okfn)(struct sk_buff ))
	359	{
9c92d348	360	return 1;
f53b61d8	361	}
f53b61d8	362	struct flowi;
eb9c7ebe	363	static inline void
76108cea JE	364	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
	365	{
	366	}
1da177e4 LT	367	#endif /CONFIG_NETFILTER/
1da177e4 LT	368
5f79e0f9	369	#if defined(CONFIG_NF_CONNTRACK) \|\| defined(CONFIG_NF_CONNTRACK_MODULE)
0e60ebe0	370	extern void (ip_ct_attach)(struct sk_buff , struct sk_buff *) __rcu;
5f79e0f9	371	extern void nf_ct_attach(struct sk_buff , struct sk_buff );
0e60ebe0	372	extern void (nf_ct_destroy)(struct nf_conntrack ) __rcu;
5f79e0f9 YK	373	#else
	374	static inline void nf_ct_attach(struct sk_buff new, struct sk_buff skb) {}
	375	#endif
	376
1da177e4 LT	377	#endif /__KERNEL__/
1da177e4 LT	378	#endif /__LINUX_NETFILTER_H/