[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / include / linux / netfilter.h

#ifndef __LINUX_NETFILTER_H
#define __LINUX_NETFILTER_H

#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>
#include <linux/static_key.h>
#include <linux/netfilter_defs.h>
#include <linux/netdevice.h>
#include <net/net_namespace.h>

#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];
}

static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
				     union nf_inet_addr *result,
				     const union nf_inet_addr *mask)
{
	result->all[0] = a1->all[0] & mask->all[0];
	result->all[1] = a1->all[1] & mask->all[1];
	result->all[2] = a1->all[2] & mask->all[2];
	result->all[3] = a1->all[3] & mask->all[3];
}

int netfilter_init(void);

struct sk_buff;

struct nf_hook_ops;

struct sock;

struct nf_hook_state {
	unsigned int hook;
	int thresh;
	u_int8_t pf;
	struct net_device *in;
	struct net_device *out;
	struct sock *sk;
	struct net *net;
	struct list_head *hook_list;
	int (*okfn)(struct net *, struct sock *, struct sk_buff *);
};

static inline void nf_hook_state_init(struct nf_hook_state *p,
				      struct list_head *hook_list,
				      unsigned int hook,
				      int thresh, u_int8_t pf,
				      struct net_device *indev,
				      struct net_device *outdev,
				      struct sock *sk,
				      struct net *net,
				      int (*okfn)(struct net *, struct sock *, struct sk_buff *))
{
	p->hook = hook;
	p->thresh = thresh;
	p->pf = pf;
	p->in = indev;
	p->out = outdev;
	p->sk = sk;
	p->net = net;
	p->hook_list = hook_list;
	p->okfn = okfn;
}

typedef unsigned int nf_hookfn(void *priv,
			       struct sk_buff *skb,
			       const struct nf_hook_state *state);

struct nf_hook_ops {
	struct list_head 	list;

	/* User fills in from here down. */
	nf_hookfn		*hook;
	struct net_device	*dev;
	void			*priv;
	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_net_hook(struct net *net, const struct nf_hook_ops *ops);
void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *ops);
int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg,
			  unsigned int n);
void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg,
			     unsigned int n);

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 HAVE_JUMP_LABEL
extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];

static inline bool nf_hook_list_active(struct list_head *hook_list,
				       u_int8_t pf, unsigned int hook)
{
	if (__builtin_constant_p(pf) &&
	    __builtin_constant_p(hook))
		return static_key_false(&nf_hooks_needed[pf][hook]);

	return !list_empty(hook_list);
}
#else
static inline bool nf_hook_list_active(struct list_head *hook_list,
				       u_int8_t pf, unsigned int hook)
{
	return !list_empty(hook_list);
}
#endif

int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state);

/**
 *	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 net *net,
				 struct sock *sk,
				 struct sk_buff *skb,
				 struct net_device *indev,
				 struct net_device *outdev,
				 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
				 int thresh)
{
	struct list_head *hook_list = &net->nf.hooks[pf][hook];

	if (nf_hook_list_active(hook_list, pf, hook)) {
		struct nf_hook_state state;

		nf_hook_state_init(&state, hook_list, hook, thresh,
				   pf, indev, outdev, sk, net, okfn);
		return nf_hook_slow(skb, &state);
	}
	return 1;
}

static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
			  struct sock *sk, struct sk_buff *skb,
			  struct net_device *indev, struct net_device *outdev,
			  int (*okfn)(struct net *, struct sock *, struct sk_buff *))
{
	return nf_hook_thresh(pf, hook, net, sk, 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 net *net, struct sock *sk,
	       struct sk_buff *skb, struct net_device *in,
	       struct net_device *out,
	       int (*okfn)(struct net *, struct sock *, struct sk_buff *),
	       int thresh)
{
	int ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, thresh);
	if (ret == 1)
		ret = okfn(net, sk, skb);
	return ret;
}

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

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

static inline int
NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb,
	struct net_device *in, struct net_device *out,
	int (*okfn)(struct net *, struct sock *, struct sk_buff *))
{
	return NF_HOOK_THRESH(pf, hook, net, sk, 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. */
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 net *net, struct dst_entry **dst,
				 struct flowi *fl, bool strict);
	void		(*saveroute)(const struct sk_buff *skb,
				     struct nf_queue_entry *entry);
	int		(*reroute)(struct net *net, 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;
}

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

#include <net/flow.h>
extern void (*nf_nat_decode_session_hook)(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 *);

	rcu_read_lock();
	decodefn = rcu_dereference(nf_nat_decode_session_hook);
	if (decodefn)
		decodefn(skb, fl);
	rcu_read_unlock();
#endif
}

#else /* !CONFIG_NETFILTER */
static inline int
NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
	     struct sk_buff *skb, struct net_device *in, struct net_device *out,
	     int (*okfn)(struct net *, struct sock *, struct sk_buff *),
	     bool cond)
{
	return okfn(net, sk, skb);
}

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

static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
			  struct sock *sk, struct sk_buff *skb,
			  struct net_device *indev, struct net_device *outdev,
			  int (*okfn)(struct net *, struct sock *, 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)
#include <linux/netfilter/nf_conntrack_zones_common.h>

extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu;
void nf_ct_attach(struct sk_buff *, const 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

struct nf_conn;
enum ip_conntrack_info;
struct nlattr;

struct nfnl_ct_hook {
	struct nf_conn *(*get_ct)(const struct sk_buff *skb,
				  enum ip_conntrack_info *ctinfo);
	size_t (*build_size)(const struct nf_conn *ct);
	int (*build)(struct sk_buff *skb, struct nf_conn *ct,
		     enum ip_conntrack_info ctinfo,
		     u_int16_t ct_attr, u_int16_t ct_info_attr);
	int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
	int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct,
			     u32 portid, u32 report);
	void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
			   enum ip_conntrack_info ctinfo, s32 off);
};
extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;

/**
 * nf_skb_duplicated - TEE target has sent a packet
 *
 * When a xtables target sends a packet, the OUTPUT and POSTROUTING
 * hooks are traversed again, i.e. nft and xtables are invoked recursively.
 *
 * This is used by xtables TEE target to prevent the duplicated skb from
 * being duplicated again.
 */
DECLARE_PER_CPU(bool, nf_skb_duplicated);

#endif /*__LINUX_NETFILTER_H*/
Commit	Line	Data
	1	#ifndef __LINUX_NETFILTER_H
	2	#define __LINUX_NETFILTER_H
	3
	4	#include <linux/init.h>
	5	#include <linux/skbuff.h>
	6	#include <linux/net.h>
	7	#include <linux/if.h>
	8	#include <linux/in.h>
	9	#include <linux/in6.h>
	10	#include <linux/wait.h>
	11	#include <linux/list.h>
	12	#include <linux/static_key.h>
	13	#include <linux/netfilter_defs.h>
	14	#include <linux/netdevice.h>
	15	#include <net/net_namespace.h>
	16
	17	#ifdef CONFIG_NETFILTER
	18	static inline int NF_DROP_GETERR(int verdict)
	19	{
	20	return -(verdict >> NF_VERDICT_QBITS);
	21	}
	22
	23	static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
	24	const union nf_inet_addr *a2)
	25	{
	26	return a1->all[0] == a2->all[0] &&
	27	a1->all[1] == a2->all[1] &&
	28	a1->all[2] == a2->all[2] &&
	29	a1->all[3] == a2->all[3];
	30	}
	31
	32	static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
	33	union nf_inet_addr *result,
	34	const union nf_inet_addr *mask)
	35	{
	36	result->all[0] = a1->all[0] & mask->all[0];
	37	result->all[1] = a1->all[1] & mask->all[1];
	38	result->all[2] = a1->all[2] & mask->all[2];
	39	result->all[3] = a1->all[3] & mask->all[3];
	40	}
	41
	42	int netfilter_init(void);
	43
	44	struct sk_buff;
	45
	46	struct nf_hook_ops;
	47
	48	struct sock;
	49
	50	struct nf_hook_state {
	51	unsigned int hook;
	52	int thresh;
	53	u_int8_t pf;
	54	struct net_device *in;
	55	struct net_device *out;
	56	struct sock *sk;
	57	struct net *net;
	58	struct list_head *hook_list;
	59	int (okfn)(struct net , struct sock , struct sk_buff );
	60	};
	61
	62	static inline void nf_hook_state_init(struct nf_hook_state *p,
	63	struct list_head *hook_list,
	64	unsigned int hook,
	65	int thresh, u_int8_t pf,
	66	struct net_device *indev,
	67	struct net_device *outdev,
	68	struct sock *sk,
	69	struct net *net,
	70	int (okfn)(struct net , struct sock , struct sk_buff ))
	71	{
	72	p->hook = hook;
	73	p->thresh = thresh;
	74	p->pf = pf;
	75	p->in = indev;
	76	p->out = outdev;
	77	p->sk = sk;
	78	p->net = net;
	79	p->hook_list = hook_list;
	80	p->okfn = okfn;
	81	}
	82
	83	typedef unsigned int nf_hookfn(void *priv,
	84	struct sk_buff *skb,
	85	const struct nf_hook_state *state);
	86
	87	struct nf_hook_ops {
	88	struct list_head list;
	89
	90	/* User fills in from here down. */
	91	nf_hookfn *hook;
	92	struct net_device *dev;
	93	void *priv;
	94	u_int8_t pf;
	95	unsigned int hooknum;
	96	/* Hooks are ordered in ascending priority. */
	97	int priority;
	98	};
	99
	100	struct nf_sockopt_ops {
	101	struct list_head list;
	102
	103	u_int8_t pf;
	104
	105	/* Non-inclusive ranges: use 0/0/NULL to never get called. */
	106	int set_optmin;
	107	int set_optmax;
	108	int (set)(struct sock sk, int optval, void __user *user, unsigned int len);
	109	#ifdef CONFIG_COMPAT
	110	int (compat_set)(struct sock sk, int optval,
	111	void __user *user, unsigned int len);
	112	#endif
	113	int get_optmin;
	114	int get_optmax;
	115	int (get)(struct sock sk, int optval, void __user user, int len);
	116	#ifdef CONFIG_COMPAT
	117	int (compat_get)(struct sock sk, int optval,
	118	void __user user, int len);
	119	#endif
	120	/* Use the module struct to lock set/get code in place */
	121	struct module *owner;
	122	};
	123
	124	/* Function to register/unregister hook points. */
	125	int nf_register_net_hook(struct net net, const struct nf_hook_ops ops);
	126	void nf_unregister_net_hook(struct net net, const struct nf_hook_ops ops);
	127	int nf_register_net_hooks(struct net net, const struct nf_hook_ops reg,
	128	unsigned int n);
	129	void nf_unregister_net_hooks(struct net net, const struct nf_hook_ops reg,
	130	unsigned int n);
	131
	132	int nf_register_hook(struct nf_hook_ops *reg);
	133	void nf_unregister_hook(struct nf_hook_ops *reg);
	134	int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
	135	void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
	136
	137	/* Functions to register get/setsockopt ranges (non-inclusive). You
	138	need to check permissions yourself! */
	139	int nf_register_sockopt(struct nf_sockopt_ops *reg);
	140	void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
	141
	142	#ifdef HAVE_JUMP_LABEL
	143	extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
	144
	145	static inline bool nf_hook_list_active(struct list_head *hook_list,
	146	u_int8_t pf, unsigned int hook)
	147	{
	148	if (__builtin_constant_p(pf) &&
	149	__builtin_constant_p(hook))
	150	return static_key_false(&nf_hooks_needed[pf][hook]);
	151
	152	return !list_empty(hook_list);
	153	}
	154	#else
	155	static inline bool nf_hook_list_active(struct list_head *hook_list,
	156	u_int8_t pf, unsigned int hook)
	157	{
	158	return !list_empty(hook_list);
	159	}
	160	#endif
	161
	162	int nf_hook_slow(struct sk_buff skb, struct nf_hook_state state);
	163
	164	/**
	165	* nf_hook_thresh - call a netfilter hook
	166	*
	167	* Returns 1 if the hook has allowed the packet to pass. The function
	168	* okfn must be invoked by the caller in this case. Any other return
	169	* value indicates the packet has been consumed by the hook.
	170	*/
	171	static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
	172	struct net *net,
	173	struct sock *sk,
	174	struct sk_buff *skb,
	175	struct net_device *indev,
	176	struct net_device *outdev,
	177	int (okfn)(struct net , struct sock , struct sk_buff ),
	178	int thresh)
	179	{
	180	struct list_head *hook_list = &net->nf.hooks[pf][hook];
	181
	182	if (nf_hook_list_active(hook_list, pf, hook)) {
	183	struct nf_hook_state state;
	184
	185	nf_hook_state_init(&state, hook_list, hook, thresh,
	186	pf, indev, outdev, sk, net, okfn);
	187	return nf_hook_slow(skb, &state);
	188	}
	189	return 1;
	190	}
	191
	192	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	193	struct sock sk, struct sk_buff skb,
	194	struct net_device indev, struct net_device outdev,
	195	int (okfn)(struct net , struct sock , struct sk_buff ))
	196	{
	197	return nf_hook_thresh(pf, hook, net, sk, skb, indev, outdev, okfn, INT_MIN);
	198	}
	199
	200	/* Activate hook; either okfn or kfree_skb called, unless a hook
	201	returns NF_STOLEN (in which case, it's up to the hook to deal with
	202	the consequences).
	203
	204	Returns -ERRNO if packet dropped. Zero means queued, stolen or
	205	accepted.
	206	*/
	207
	208	/* RR:
	209	> I don't want nf_hook to return anything because people might forget
	210	> about async and trust the return value to mean "packet was ok".
	211
	212	AK:
	213	Just document it clearly, then you can expect some sense from kernel
	214	coders :)
	215	*/
	216
	217	static inline int
	218	NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	219	struct sk_buff skb, struct net_device in,
	220	struct net_device *out,
	221	int (okfn)(struct net , struct sock , struct sk_buff ),
	222	int thresh)
	223	{
	224	int ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, thresh);
	225	if (ret == 1)
	226	ret = okfn(net, sk, skb);
	227	return ret;
	228	}
	229
	230	static inline int
	231	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	232	struct sk_buff skb, struct net_device in, struct net_device *out,
	233	int (okfn)(struct net , struct sock , struct sk_buff ),
	234	bool cond)
	235	{
	236	int ret;
	237
	238	if (!cond \|\|
	239	((ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, INT_MIN)) == 1))
	240	ret = okfn(net, sk, skb);
	241	return ret;
	242	}
	243
	244	static inline int
	245	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk, struct sk_buff *skb,
	246	struct net_device in, struct net_device out,
	247	int (okfn)(struct net , struct sock , struct sk_buff ))
	248	{
	249	return NF_HOOK_THRESH(pf, hook, net, sk, skb, in, out, okfn, INT_MIN);
	250	}
	251
	252	/* Call setsockopt() */
	253	int nf_setsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
	254	unsigned int len);
	255	int nf_getsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
	256	int *len);
	257	#ifdef CONFIG_COMPAT
	258	int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
	259	char __user *opt, unsigned int len);
	260	int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
	261	char __user opt, int len);
	262	#endif
	263
	264	/* Call this before modifying an existing packet: ensures it is
	265	modifiable and linear to the point you care about (writable_len).
	266	Returns true or false. */
	267	int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
	268
	269	struct flowi;
	270	struct nf_queue_entry;
	271
	272	struct nf_afinfo {
	273	unsigned short family;
	274	__sum16 (checksum)(struct sk_buff skb, unsigned int hook,
	275	unsigned int dataoff, u_int8_t protocol);
	276	__sum16 (checksum_partial)(struct sk_buff skb,
	277	unsigned int hook,
	278	unsigned int dataoff,
	279	unsigned int len,
	280	u_int8_t protocol);
	281	int (route)(struct net net, struct dst_entry **dst,
	282	struct flowi *fl, bool strict);
	283	void (saveroute)(const struct sk_buff skb,
	284	struct nf_queue_entry *entry);
	285	int (reroute)(struct net net, struct sk_buff *skb,
	286	const struct nf_queue_entry *entry);
	287	int route_key_size;
	288	};
	289
	290	extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
	291	static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
	292	{
	293	return rcu_dereference(nf_afinfo[family]);
	294	}
	295
	296	static inline __sum16
	297	nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
	298	u_int8_t protocol, unsigned short family)
	299	{
	300	const struct nf_afinfo *afinfo;
	301	__sum16 csum = 0;
	302
	303	rcu_read_lock();
	304	afinfo = nf_get_afinfo(family);
	305	if (afinfo)
	306	csum = afinfo->checksum(skb, hook, dataoff, protocol);
	307	rcu_read_unlock();
	308	return csum;
	309	}
	310
	311	static inline __sum16
	312	nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
	313	unsigned int dataoff, unsigned int len,
	314	u_int8_t protocol, unsigned short family)
	315	{
	316	const struct nf_afinfo *afinfo;
	317	__sum16 csum = 0;
	318
	319	rcu_read_lock();
	320	afinfo = nf_get_afinfo(family);
	321	if (afinfo)
	322	csum = afinfo->checksum_partial(skb, hook, dataoff, len,
	323	protocol);
	324	rcu_read_unlock();
	325	return csum;
	326	}
	327
	328	int nf_register_afinfo(const struct nf_afinfo *afinfo);
	329	void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
	330
	331	#include <net/flow.h>
	332	extern void (nf_nat_decode_session_hook)(struct sk_buff , struct flowi *);
	333
	334	static inline void
	335	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
	336	{
	337	#ifdef CONFIG_NF_NAT_NEEDED
	338	void (decodefn)(struct sk_buff , struct flowi *);
	339
	340	rcu_read_lock();
	341	decodefn = rcu_dereference(nf_nat_decode_session_hook);
	342	if (decodefn)
	343	decodefn(skb, fl);
	344	rcu_read_unlock();
	345	#endif
	346	}
	347
	348	#else /* !CONFIG_NETFILTER */
	349	static inline int
	350	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	351	struct sk_buff skb, struct net_device in, struct net_device *out,
	352	int (okfn)(struct net , struct sock , struct sk_buff ),
	353	bool cond)
	354	{
	355	return okfn(net, sk, skb);
	356	}
	357
	358	static inline int
	359	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	360	struct sk_buff skb, struct net_device in, struct net_device *out,
	361	int (okfn)(struct net , struct sock , struct sk_buff ))
	362	{
	363	return okfn(net, sk, skb);
	364	}
	365
	366	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	367	struct sock sk, struct sk_buff skb,
	368	struct net_device indev, struct net_device outdev,
	369	int (okfn)(struct net , struct sock , struct sk_buff ))
	370	{
	371	return 1;
	372	}
	373	struct flowi;
	374	static inline void
	375	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
	376	{
	377	}
	378	#endif /CONFIG_NETFILTER/
	379
	380	#if defined(CONFIG_NF_CONNTRACK) \|\| defined(CONFIG_NF_CONNTRACK_MODULE)
	381	#include <linux/netfilter/nf_conntrack_zones_common.h>
	382
	383	extern void (ip_ct_attach)(struct sk_buff , const struct sk_buff *) __rcu;
	384	void nf_ct_attach(struct sk_buff , const struct sk_buff );
	385	extern void (nf_ct_destroy)(struct nf_conntrack ) __rcu;
	386	#else
	387	static inline void nf_ct_attach(struct sk_buff new, struct sk_buff skb) {}
	388	#endif
	389
	390	struct nf_conn;
	391	enum ip_conntrack_info;
	392	struct nlattr;
	393
	394	struct nfnl_ct_hook {
	395	struct nf_conn (get_ct)(const struct sk_buff *skb,
	396	enum ip_conntrack_info *ctinfo);
	397	size_t (build_size)(const struct nf_conn ct);
	398	int (build)(struct sk_buff skb, struct nf_conn *ct,
	399	enum ip_conntrack_info ctinfo,
	400	u_int16_t ct_attr, u_int16_t ct_info_attr);
	401	int (parse)(const struct nlattr attr, struct nf_conn *ct);
	402	int (attach_expect)(const struct nlattr attr, struct nf_conn *ct,
	403	u32 portid, u32 report);
	404	void (seq_adjust)(struct sk_buff skb, struct nf_conn *ct,
	405	enum ip_conntrack_info ctinfo, s32 off);
	406	};
	407	extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
	408
	409	/**
	410	* nf_skb_duplicated - TEE target has sent a packet
	411	*
	412	* When a xtables target sends a packet, the OUTPUT and POSTROUTING
	413	* hooks are traversed again, i.e. nft and xtables are invoked recursively.
	414	*
	415	* This is used by xtables TEE target to prevent the duplicated skb from
	416	* being duplicated again.
	417	*/
	418	DECLARE_PER_CPU(bool, nf_skb_duplicated);
	419
	420	#endif /__LINUX_NETFILTER_H/