[mirror_ubuntu-artful-kernel.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;
	u_int8_t pf;
	struct net_device *in;
	struct net_device *out;
	struct sock *sk;
	struct net *net;
	int (*okfn)(struct net *, struct sock *, struct sk_buff *);
};

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_hook_entry {
	struct nf_hook_entry __rcu	*next;
	nf_hookfn			*hook;
	void				*priv;
	const struct nf_hook_ops	*orig_ops;
};

static inline void
nf_hook_entry_init(struct nf_hook_entry *entry,	const struct nf_hook_ops *ops)
{
	entry->next = NULL;
	entry->hook = ops->hook;
	entry->priv = ops->priv;
	entry->orig_ops = ops;
}

static inline int
nf_hook_entry_priority(const struct nf_hook_entry *entry)
{
	return entry->orig_ops->priority;
}

static inline int
nf_hook_entry_hookfn(const struct nf_hook_entry *entry, struct sk_buff *skb,
		     struct nf_hook_state *state)
{
	return entry->hook(entry->priv, skb, state);
}

static inline const struct nf_hook_ops *
nf_hook_entry_ops(const struct nf_hook_entry *entry)
{
	return entry->orig_ops;
}

static inline void nf_hook_state_init(struct nf_hook_state *p,
				      unsigned int hook,
				      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->pf = pf;
	p->in = indev;
	p->out = outdev;
	p->sk = sk;
	p->net = net;
	p->okfn = okfn;
}


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);
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];
#endif

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

/**
 *	nf_hook - 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(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 *))
{
	struct nf_hook_entry *hook_head;
	int ret = 1;

#ifdef HAVE_JUMP_LABEL
	if (__builtin_constant_p(pf) &&
	    __builtin_constant_p(hook) &&
	    !static_key_false(&nf_hooks_needed[pf][hook]))
		return 1;
#endif

	rcu_read_lock();
	hook_head = rcu_dereference(net->nf.hooks[pf][hook]);
	if (hook_head) {
		struct nf_hook_state state;

		nf_hook_state_init(&state, hook, pf, indev, outdev,
				   sk, net, okfn);

		ret = nf_hook_slow(skb, &state, hook_head);
	}
	rcu_read_unlock();

	return ret;
}

/* 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_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(pf, hook, net, sk, skb, in, out, okfn)) == 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 *))
{
	int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
	if (ret == 1)
		ret = okfn(net, sk, skb);
	return ret;
}

/* 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
1da177e4 LT	1	#ifndef __LINUX_NETFILTER_H
	2	#define __LINUX_NETFILTER_H
	3
1da177e4	4	#include <linux/init.h>
1da177e4 LT	5	#include <linux/skbuff.h>
	6	#include <linux/net.h>
	7	#include <linux/if.h>
2e3075a2 JE	8	#include <linux/in.h>
2e3075a2 JE	9	#include <linux/in6.h>
1da177e4 LT	10	#include <linux/wait.h>
1da177e4 LT	11	#include <linux/list.h>
d1c85c2e	12	#include <linux/static_key.h>
a263653e	13	#include <linux/netfilter_defs.h>
085db2c0 EB	14	#include <linux/netdevice.h>
085db2c0 EB	15	#include <net/net_namespace.h>
a263653e	16
1da177e4	17	#ifdef CONFIG_NETFILTER
f615df76 FW	18	static inline int NF_DROP_GETERR(int verdict)
	19	{
	20	return -(verdict >> NF_VERDICT_QBITS);
	21	}
1da177e4	22
b8beedd2 PM	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
efdedd54 DF	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
a0f4ecf3	42	int netfilter_init(void);
1da177e4	43
1da177e4	44	struct sk_buff;
1da177e4	45
795aa6ef	46	struct nf_hook_ops;
cfdfab31	47
1c984f8a DM	48	struct sock;
1c984f8a DM	49
cfdfab31 DM	50	struct nf_hook_state {
cfdfab31 DM	51	unsigned int hook;
cfdfab31 DM	52	u_int8_t pf;
	53	struct net_device *in;
	54	struct net_device *out;
1c984f8a	55	struct sock *sk;
b11b1f65	56	struct net *net;
0c4b51f0	57	int (okfn)(struct net , struct sock , struct sk_buff );
cfdfab31 DM	58	};
cfdfab31 DM	59
e3b37f11 AC	60	typedef unsigned int nf_hookfn(void *priv,
	61	struct sk_buff *skb,
	62	const struct nf_hook_state *state);
	63	struct nf_hook_ops {
	64	struct list_head list;
	65
	66	/* User fills in from here down. */
	67	nf_hookfn *hook;
	68	struct net_device *dev;
	69	void *priv;
	70	u_int8_t pf;
	71	unsigned int hooknum;
	72	/* Hooks are ordered in ascending priority. */
	73	int priority;
	74	};
	75
	76	struct nf_hook_entry {
	77	struct nf_hook_entry __rcu *next;
d415b9eb AC	78	nf_hookfn *hook;
d415b9eb AC	79	void *priv;
e3b37f11 AC	80	const struct nf_hook_ops *orig_ops;
	81	};
	82
0aa8c57a AC	83	static inline void
	84	nf_hook_entry_init(struct nf_hook_entry entry, const struct nf_hook_ops ops)
	85	{
	86	entry->next = NULL;
d415b9eb AC	87	entry->hook = ops->hook;
d415b9eb AC	88	entry->priv = ops->priv;
0aa8c57a AC	89	entry->orig_ops = ops;
	90	}
	91
	92	static inline int
	93	nf_hook_entry_priority(const struct nf_hook_entry *entry)
	94	{
d415b9eb	95	return entry->orig_ops->priority;
0aa8c57a AC	96	}
	97
	98	static inline int
	99	nf_hook_entry_hookfn(const struct nf_hook_entry entry, struct sk_buff skb,
	100	struct nf_hook_state *state)
	101	{
d415b9eb	102	return entry->hook(entry->priv, skb, state);
0aa8c57a AC	103	}
	104
	105	static inline const struct nf_hook_ops *
	106	nf_hook_entry_ops(const struct nf_hook_entry *entry)
	107	{
	108	return entry->orig_ops;
	109	}
	110
107a9f4d DM	111	static inline void nf_hook_state_init(struct nf_hook_state *p,
107a9f4d DM	112	unsigned int hook,
1610a73c	113	u_int8_t pf,
107a9f4d DM	114	struct net_device *indev,
107a9f4d DM	115	struct net_device *outdev,
1c984f8a	116	struct sock *sk,
b11b1f65	117	struct net *net,
0c4b51f0	118	int (okfn)(struct net , struct sock , struct sk_buff ))
107a9f4d DM	119	{
107a9f4d DM	120	p->hook = hook;
107a9f4d DM	121	p->pf = pf;
	122	p->in = indev;
	123	p->out = outdev;
1c984f8a	124	p->sk = sk;
b11b1f65	125	p->net = net;
107a9f4d DM	126	p->okfn = okfn;
	127	}
	128
1da177e4	129
1da177e4	130
d94d9fee	131	struct nf_sockopt_ops {
1da177e4 LT	132	struct list_head list;
1da177e4 LT	133
76108cea	134	u_int8_t pf;
1da177e4 LT	135
	136	/* Non-inclusive ranges: use 0/0/NULL to never get called. */
	137	int set_optmin;
	138	int set_optmax;
	139	int (set)(struct sock sk, int optval, void __user *user, unsigned int len);
c30f540b	140	#ifdef CONFIG_COMPAT
3fdadf7d DM	141	int (compat_set)(struct sock sk, int optval,
3fdadf7d DM	142	void __user *user, unsigned int len);
c30f540b	143	#endif
1da177e4 LT	144	int get_optmin;
	145	int get_optmax;
	146	int (get)(struct sock sk, int optval, void __user user, int len);
c30f540b	147	#ifdef CONFIG_COMPAT
3fdadf7d DM	148	int (compat_get)(struct sock sk, int optval,
3fdadf7d DM	149	void __user user, int len);
c30f540b	150	#endif
16fcec35 NH	151	/* Use the module struct to lock set/get code in place */
16fcec35 NH	152	struct module *owner;
1da177e4 LT	153	};
1da177e4 LT	154
1da177e4	155	/* Function to register/unregister hook points. */
085db2c0 EB	156	int nf_register_net_hook(struct net net, const struct nf_hook_ops ops);
	157	void nf_unregister_net_hook(struct net net, const struct nf_hook_ops ops);
	158	int nf_register_net_hooks(struct net net, const struct nf_hook_ops reg,
	159	unsigned int n);
	160	void nf_unregister_net_hooks(struct net net, const struct nf_hook_ops reg,
	161	unsigned int n);
	162
1da177e4 LT	163	int nf_register_hook(struct nf_hook_ops *reg);
1da177e4 LT	164	void nf_unregister_hook(struct nf_hook_ops *reg);
972d1cb1 PM	165	int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
972d1cb1 PM	166	void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
e8bffe0c MB	167	int _nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
e8bffe0c MB	168	void _nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
1da177e4 LT	169
	170	/* Functions to register get/setsockopt ranges (non-inclusive). You
	171	need to check permissions yourself! */
	172	int nf_register_sockopt(struct nf_sockopt_ops *reg);
	173	void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
	174
d1c85c2e	175	#ifdef HAVE_JUMP_LABEL
c5905afb	176	extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
a2d7ec58 ED	177	#endif
a2d7ec58 ED	178
01886bd9 PNA	179	int nf_hook_slow(struct sk_buff skb, struct nf_hook_state state,
01886bd9 PNA	180	struct nf_hook_entry *entry);
16a6677f PM	181
16a6677f PM	182	/**
1610a73c	183	* nf_hook - call a netfilter hook
b8d0aad0	184	*
16a6677f PM	185	* Returns 1 if the hook has allowed the packet to pass. The function
	186	* okfn must be invoked by the caller in this case. Any other return
	187	* value indicates the packet has been consumed by the hook.
	188	*/
1610a73c PNA	189	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	190	struct sock sk, struct sk_buff skb,
	191	struct net_device indev, struct net_device outdev,
	192	int (okfn)(struct net , struct sock , struct sk_buff ))
16a6677f	193	{
e3b37f11 AC	194	struct nf_hook_entry *hook_head;
e3b37f11 AC	195	int ret = 1;
af4610c3 FW	196
	197	#ifdef HAVE_JUMP_LABEL
	198	if (__builtin_constant_p(pf) &&
	199	__builtin_constant_p(hook) &&
	200	!static_key_false(&nf_hooks_needed[pf][hook]))
	201	return 1;
	202	#endif
	203
e3b37f11 AC	204	rcu_read_lock();
	205	hook_head = rcu_dereference(net->nf.hooks[pf][hook]);
	206	if (hook_head) {
107a9f4d	207	struct nf_hook_state state;
cfdfab31	208
01886bd9	209	nf_hook_state_init(&state, hook, pf, indev, outdev,
1610a73c	210	sk, net, okfn);
fe72926b	211
01886bd9	212	ret = nf_hook_slow(skb, &state, hook_head);
cfdfab31	213	}
e3b37f11 AC	214	rcu_read_unlock();
	215
	216	return ret;
16a6677f PM	217	}
16a6677f PM	218
1da177e4 LT	219	/* Activate hook; either okfn or kfree_skb called, unless a hook
	220	returns NF_STOLEN (in which case, it's up to the hook to deal with
	221	the consequences).
	222
	223	Returns -ERRNO if packet dropped. Zero means queued, stolen or
	224	accepted.
	225	*/
	226
	227	/* RR:
	228	> I don't want nf_hook to return anything because people might forget
	229	> about async and trust the return value to mean "packet was ok".
	230
	231	AK:
	232	Just document it clearly, then you can expect some sense from kernel
	233	coders :)
	234	*/
	235
2249065f	236	static inline int
29a26a56	237	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
7026b1dd	238	struct sk_buff skb, struct net_device in, struct net_device *out,
0c4b51f0 EB	239	int (okfn)(struct net , struct sock , struct sk_buff ),
0c4b51f0 EB	240	bool cond)
2249065f	241	{
4bac6b18 PM	242	int ret;
	243
	244	if (!cond \|\|
1610a73c	245	((ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn)) == 1))
0c4b51f0	246	ret = okfn(net, sk, skb);
2249065f JE	247	return ret;
2249065f JE	248	}
1da177e4	249
2249065f	250	static inline int
29a26a56	251	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk, struct sk_buff *skb,
2249065f	252	struct net_device in, struct net_device out,
0c4b51f0	253	int (okfn)(struct net , struct sock , struct sk_buff ))
2249065f	254	{
1610a73c PNA	255	int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
	256	if (ret == 1)
	257	ret = okfn(net, sk, skb);
	258	return ret;
2249065f	259	}
1da177e4 LT	260
1da177e4 LT	261	/* Call setsockopt() */
76108cea	262	int nf_setsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
b7058842	263	unsigned int len);
76108cea	264	int nf_getsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
1da177e4	265	int *len);
c30f540b	266	#ifdef CONFIG_COMPAT
76108cea	267	int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
b7058842	268	char __user *opt, unsigned int len);
76108cea	269	int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
3fdadf7d	270	char __user opt, int len);
c30f540b	271	#endif
3fdadf7d	272
089af26c HW	273	/* Call this before modifying an existing packet: ensures it is
	274	modifiable and linear to the point you care about (writable_len).
	275	Returns true or false. */
a0f4ecf3	276	int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
089af26c	277
1841a4c7	278	struct flowi;
02f014d8	279	struct nf_queue_entry;
c01cd429	280
bce8032e PM	281	struct nf_afinfo {
bce8032e PM	282	unsigned short family;
b51655b9	283	__sum16 (checksum)(struct sk_buff skb, unsigned int hook,
422c346f	284	unsigned int dataoff, u_int8_t protocol);
d63a6507 PM	285	__sum16 (checksum_partial)(struct sk_buff skb,
	286	unsigned int hook,
	287	unsigned int dataoff,
	288	unsigned int len,
	289	u_int8_t protocol);
31ad3dd6	290	int (route)(struct net net, struct dst_entry **dst,
0fae2e77	291	struct flowi *fl, bool strict);
bce8032e	292	void (saveroute)(const struct sk_buff skb,
02f014d8	293	struct nf_queue_entry *entry);
d815d90b	294	int (reroute)(struct net net, struct sk_buff *skb,
02f014d8	295	const struct nf_queue_entry *entry);
bce8032e	296	int route_key_size;
2cc7d573 HW	297	};
2cc7d573 HW	298
0e60ebe0	299	extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
1e796fda	300	static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
bce8032e PM	301	{
	302	return rcu_dereference(nf_afinfo[family]);
	303	}
2cc7d573	304
b51655b9	305	static inline __sum16
422c346f PM	306	nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
	307	u_int8_t protocol, unsigned short family)
	308	{
1e796fda	309	const struct nf_afinfo *afinfo;
b51655b9	310	__sum16 csum = 0;
422c346f PM	311
	312	rcu_read_lock();
	313	afinfo = nf_get_afinfo(family);
	314	if (afinfo)
	315	csum = afinfo->checksum(skb, hook, dataoff, protocol);
	316	rcu_read_unlock();
	317	return csum;
	318	}
	319
d63a6507 PM	320	static inline __sum16
	321	nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
	322	unsigned int dataoff, unsigned int len,
	323	u_int8_t protocol, unsigned short family)
	324	{
	325	const struct nf_afinfo *afinfo;
	326	__sum16 csum = 0;
	327
	328	rcu_read_lock();
	329	afinfo = nf_get_afinfo(family);
	330	if (afinfo)
	331	csum = afinfo->checksum_partial(skb, hook, dataoff, len,
	332	protocol);
	333	rcu_read_unlock();
	334	return csum;
	335	}
	336
a0f4ecf3 JP	337	int nf_register_afinfo(const struct nf_afinfo *afinfo);
a0f4ecf3 JP	338	void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
bce8032e	339
eb9c7ebe	340	#include <net/flow.h>
c7232c99	341	extern void (nf_nat_decode_session_hook)(struct sk_buff , struct flowi *);
eb9c7ebe PM	342
eb9c7ebe PM	343	static inline void
76108cea	344	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
eb9c7ebe	345	{
051578cc	346	#ifdef CONFIG_NF_NAT_NEEDED
eb9c7ebe PM	347	void (decodefn)(struct sk_buff , struct flowi *);
eb9c7ebe PM	348
c7232c99 PM	349	rcu_read_lock();
	350	decodefn = rcu_dereference(nf_nat_decode_session_hook);
	351	if (decodefn)
	352	decodefn(skb, fl);
	353	rcu_read_unlock();
eb9c7ebe PM	354	#endif
	355	}
	356
1da177e4	357	#else /* !CONFIG_NETFILTER */
008027c3 AB	358	static inline int
	359	NF_HOOK_COND(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	bool cond)
	363	{
	364	return okfn(net, sk, skb);
	365	}
	366
	367	static inline int
	368	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	369	struct sk_buff skb, struct net_device in, struct net_device *out,
	370	int (okfn)(struct net , struct sock , struct sk_buff ))
	371	{
	372	return okfn(net, sk, skb);
	373	}
	374
29a26a56 EB	375	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	376	struct sock sk, struct sk_buff skb,
	377	struct net_device indev, struct net_device outdev,
0c4b51f0	378	int (okfn)(struct net , struct sock , struct sk_buff ))
f53b61d8	379	{
9c92d348	380	return 1;
f53b61d8	381	}
f53b61d8	382	struct flowi;
eb9c7ebe	383	static inline void
76108cea JE	384	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
	385	{
	386	}
1da177e4 LT	387	#endif /CONFIG_NETFILTER/
1da177e4 LT	388
5f79e0f9	389	#if defined(CONFIG_NF_CONNTRACK) \|\| defined(CONFIG_NF_CONNTRACK_MODULE)
62da9865 DB	390	#include <linux/netfilter/nf_conntrack_zones_common.h>
62da9865 DB	391
312a0c16	392	extern void (ip_ct_attach)(struct sk_buff , const struct sk_buff *) __rcu;
a0f4ecf3	393	void nf_ct_attach(struct sk_buff , const struct sk_buff );
0e60ebe0	394	extern void (nf_ct_destroy)(struct nf_conntrack ) __rcu;
b7bd1809 PNA	395	#else
	396	static inline void nf_ct_attach(struct sk_buff new, struct sk_buff skb) {}
	397	#endif
9cb01766 PNA	398
9cb01766 PNA	399	struct nf_conn;
41d73ec0	400	enum ip_conntrack_info;
9cb01766 PNA	401	struct nlattr;
9cb01766 PNA	402
a4b4766c	403	struct nfnl_ct_hook {
224a0597	404	struct nf_conn (get_ct)(const struct sk_buff *skb,
b7bd1809	405	enum ip_conntrack_info *ctinfo);
9cb01766	406	size_t (build_size)(const struct nf_conn ct);
b7bd1809 PNA	407	int (build)(struct sk_buff skb, struct nf_conn *ct,
	408	enum ip_conntrack_info ctinfo,
	409	u_int16_t ct_attr, u_int16_t ct_info_attr);
9cb01766	410	int (parse)(const struct nlattr attr, struct nf_conn *ct);
bd077937 PNA	411	int (attach_expect)(const struct nlattr attr, struct nf_conn *ct,
bd077937 PNA	412	u32 portid, u32 report);
8c88f87c	413	void (seq_adjust)(struct sk_buff skb, struct nf_conn *ct,
41d73ec0	414	enum ip_conntrack_info ctinfo, s32 off);
9cb01766	415	};
a4b4766c	416	extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
5f79e0f9	417
e7c8899f FW	418	/**
	419	* nf_skb_duplicated - TEE target has sent a packet
	420	*
	421	* When a xtables target sends a packet, the OUTPUT and POSTROUTING
	422	* hooks are traversed again, i.e. nft and xtables are invoked recursively.
	423	*
	424	* This is used by xtables TEE target to prevent the duplicated skb from
	425	* being duplicated again.
	426	*/
	427	DECLARE_PER_CPU(bool, nf_skb_duplicated);
	428
1da177e4	429	#endif /__LINUX_NETFILTER_H/