[linux-block.git] / include / linux / netfilter.h

/* SPDX-License-Identifier: GPL-2.0 */
#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 <linux/sockptr.h>
#include <net/net_namespace.h>

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)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul1 = (const unsigned long *)a1;
	const unsigned long *ul2 = (const unsigned long *)a2;

	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
#else
	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];
#endif
}

static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
				     union nf_inet_addr *result,
				     const union nf_inet_addr *mask)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ua = (const unsigned long *)a1;
	unsigned long *ur = (unsigned long *)result;
	const unsigned long *um = (const unsigned long *)mask;

	ur[0] = ua[0] & um[0];
	ur[1] = ua[1] & um[1];
#else
	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];
#endif
}

int netfilter_init(void);

struct sk_buff;

struct nf_hook_ops;

struct sock;

struct nf_hook_state {
	u8 hook;
	u8 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);
enum nf_hook_ops_type {
	NF_HOOK_OP_UNDEFINED,
	NF_HOOK_OP_NF_TABLES,
};

struct nf_hook_ops {
	/* User fills in from here down. */
	nf_hookfn		*hook;
	struct net_device	*dev;
	void			*priv;
	u8			pf;
	enum nf_hook_ops_type	hook_ops_type:8;
	unsigned int		hooknum;
	/* Hooks are ordered in ascending priority. */
	int			priority;
};

struct nf_hook_entry {
	nf_hookfn			*hook;
	void				*priv;
};

struct nf_hook_entries_rcu_head {
	struct rcu_head head;
	void	*allocation;
};

struct nf_hook_entries {
	u16				num_hook_entries;
	/* padding */
	struct nf_hook_entry		hooks[];

	/* trailer: pointers to original orig_ops of each hook,
	 * followed by rcu_head and scratch space used for freeing
	 * the structure via call_rcu.
	 *
	 *   This is not part of struct nf_hook_entry since its only
	 *   needed in slow path (hook register/unregister):
	 * const struct nf_hook_ops     *orig_ops[]
	 *
	 *   For the same reason, we store this at end -- its
	 *   only needed when a hook is deleted, not during
	 *   packet path processing:
	 * struct nf_hook_entries_rcu_head     head
	 */
};

#ifdef CONFIG_NETFILTER
static inline struct nf_hook_ops **nf_hook_entries_get_hook_ops(const struct nf_hook_entries *e)
{
	unsigned int n = e->num_hook_entries;
	const void *hook_end;

	hook_end = &e->hooks[n]; /* this is *past* ->hooks[]! */

	return (struct nf_hook_ops **)hook_end;
}

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 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, sockptr_t arg,
		   unsigned int len);
	int get_optmin;
	int get_optmax;
	int (*get)(struct sock *sk, int optval, void __user *user, int *len);
	/* 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);

/* 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_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,
		 const struct nf_hook_entries *e, unsigned int i);

void nf_hook_slow_list(struct list_head *head, struct nf_hook_state *state,
		       const struct nf_hook_entries *e);
/**
 *	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_entries *hook_head = NULL;
	int ret = 1;

#ifdef CONFIG_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();
	switch (pf) {
	case NFPROTO_IPV4:
		hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
		break;
	case NFPROTO_IPV6:
		hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
		break;
	case NFPROTO_ARP:
#ifdef CONFIG_NETFILTER_FAMILY_ARP
		if (WARN_ON_ONCE(hook >= ARRAY_SIZE(net->nf.hooks_arp)))
			break;
		hook_head = rcu_dereference(net->nf.hooks_arp[hook]);
#endif
		break;
	case NFPROTO_BRIDGE:
#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
		hook_head = rcu_dereference(net->nf.hooks_bridge[hook]);
#endif
		break;
#if IS_ENABLED(CONFIG_DECNET)
	case NFPROTO_DECNET:
		hook_head = rcu_dereference(net->nf.hooks_decnet[hook]);
		break;
#endif
	default:
		WARN_ON_ONCE(1);
		break;
	}

	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, 0);
	}
	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;
}

static inline void
NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
	     struct list_head *head, struct net_device *in, struct net_device *out,
	     int (*okfn)(struct net *, struct sock *, struct sk_buff *))
{
	struct nf_hook_entries *hook_head = NULL;

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

	rcu_read_lock();
	switch (pf) {
	case NFPROTO_IPV4:
		hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
		break;
	case NFPROTO_IPV6:
		hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
		break;
	default:
		WARN_ON_ONCE(1);
		break;
	}

	if (hook_head) {
		struct nf_hook_state state;

		nf_hook_state_init(&state, hook, pf, in, out, sk, net, okfn);

		nf_hook_slow_list(head, &state, hook_head);
	}
	rcu_read_unlock();
}

/* Call setsockopt() */
int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, sockptr_t opt,
		  unsigned int len);
int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
		  int *len);

struct flowi;
struct nf_queue_entry;

__sum16 nf_checksum(struct sk_buff *skb, unsigned int hook,
		    unsigned int dataoff, u_int8_t protocol,
		    unsigned short family);

__sum16 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
			    unsigned int dataoff, unsigned int len,
			    u_int8_t protocol, unsigned short family);
int nf_route(struct net *net, struct dst_entry **dst, struct flowi *fl,
	     bool strict, unsigned short family);
int nf_reroute(struct sk_buff *skb, struct nf_queue_entry *entry);

#include <net/flow.h>

struct nf_conn;
enum nf_nat_manip_type;
struct nlattr;
enum ip_conntrack_dir;

struct nf_nat_hook {
	int (*parse_nat_setup)(struct nf_conn *ct, enum nf_nat_manip_type manip,
			       const struct nlattr *attr);
	void (*decode_session)(struct sk_buff *skb, struct flowi *fl);
	unsigned int (*manip_pkt)(struct sk_buff *skb, struct nf_conn *ct,
				  enum nf_nat_manip_type mtype,
				  enum ip_conntrack_dir dir);
	void (*remove_nat_bysrc)(struct nf_conn *ct);
};

extern const struct nf_nat_hook __rcu *nf_nat_hook;

static inline void
nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
{
#if IS_ENABLED(CONFIG_NF_NAT)
	const struct nf_nat_hook *nat_hook;

	rcu_read_lock();
	nat_hook = rcu_dereference(nf_nat_hook);
	if (nat_hook && nat_hook->decode_session)
		nat_hook->decode_session(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 void
NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
	     struct list_head *head, struct net_device *in, struct net_device *out,
	     int (*okfn)(struct net *, struct sock *, struct sk_buff *))
{
	/* nothing to do */
}

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 IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <linux/netfilter/nf_conntrack_zones_common.h>

void nf_ct_attach(struct sk_buff *, const struct sk_buff *);
struct nf_conntrack_tuple;
bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
			 const struct sk_buff *skb);
#else
static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
struct nf_conntrack_tuple;
static inline bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
				       const struct sk_buff *skb)
{
	return false;
}
#endif

struct nf_conn;
enum ip_conntrack_info;

struct nf_ct_hook {
	int (*update)(struct net *net, struct sk_buff *skb);
	void (*destroy)(struct nf_conntrack *);
	bool (*get_tuple_skb)(struct nf_conntrack_tuple *,
			      const struct sk_buff *);
	void (*attach)(struct sk_buff *nskb, const struct sk_buff *skb);
};
extern const struct nf_ct_hook __rcu *nf_ct_hook;

struct nlattr;

struct nfnl_ct_hook {
	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 const 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
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 LT	2	#ifndef __LINUX_NETFILTER_H
	3	#define __LINUX_NETFILTER_H
	4
1da177e4	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>
1da177e4 LT	12	#include <linux/list.h>
d1c85c2e	13	#include <linux/static_key.h>
a263653e	14	#include <linux/netfilter_defs.h>
085db2c0	15	#include <linux/netdevice.h>
c2f12630	16	#include <linux/sockptr.h>
085db2c0	17	#include <net/net_namespace.h>
a263653e	18
f615df76 FW	19	static inline int NF_DROP_GETERR(int verdict)
	20	{
	21	return -(verdict >> NF_VERDICT_QBITS);
	22	}
1da177e4	23
b8beedd2 PM	24	static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
	25	const union nf_inet_addr *a2)
	26	{
01902f8c LR	27	#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	28	const unsigned long ul1 = (const unsigned long )a1;
	29	const unsigned long ul2 = (const unsigned long )a2;
	30
	31	return ((ul1[0] ^ ul2[0]) \| (ul1[1] ^ ul2[1])) == 0UL;
	32	#else
b8beedd2 PM	33	return a1->all[0] == a2->all[0] &&
	34	a1->all[1] == a2->all[1] &&
	35	a1->all[2] == a2->all[2] &&
	36	a1->all[3] == a2->all[3];
01902f8c	37	#endif
b8beedd2 PM	38	}
b8beedd2 PM	39
efdedd54 DF	40	static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
	41	union nf_inet_addr *result,
	42	const union nf_inet_addr *mask)
	43	{
522e4077 LR	44	#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	45	const unsigned long ua = (const unsigned long )a1;
	46	unsigned long ur = (unsigned long )result;
	47	const unsigned long um = (const unsigned long )mask;
	48
	49	ur[0] = ua[0] & um[0];
	50	ur[1] = ua[1] & um[1];
	51	#else
efdedd54 DF	52	result->all[0] = a1->all[0] & mask->all[0];
	53	result->all[1] = a1->all[1] & mask->all[1];
	54	result->all[2] = a1->all[2] & mask->all[2];
	55	result->all[3] = a1->all[3] & mask->all[3];
522e4077	56	#endif
efdedd54 DF	57	}
efdedd54 DF	58
a0f4ecf3	59	int netfilter_init(void);
1da177e4	60
1da177e4	61	struct sk_buff;
1da177e4	62
795aa6ef	63	struct nf_hook_ops;
cfdfab31	64
1c984f8a DM	65	struct sock;
1c984f8a DM	66
cfdfab31	67	struct nf_hook_state {
6802db48 FW	68	u8 hook;
6802db48 FW	69	u8 pf;
cfdfab31 DM	70	struct net_device *in;
cfdfab31 DM	71	struct net_device *out;
1c984f8a	72	struct sock *sk;
b11b1f65	73	struct net *net;
0c4b51f0	74	int (okfn)(struct net , struct sock , struct sk_buff );
cfdfab31 DM	75	};
cfdfab31 DM	76
e3b37f11 AC	77	typedef unsigned int nf_hookfn(void *priv,
	78	struct sk_buff *skb,
	79	const struct nf_hook_state *state);
7b4b2fa3 FW	80	enum nf_hook_ops_type {
	81	NF_HOOK_OP_UNDEFINED,
	82	NF_HOOK_OP_NF_TABLES,
	83	};
	84
e3b37f11	85	struct nf_hook_ops {
e3b37f11 AC	86	/* User fills in from here down. */
	87	nf_hookfn *hook;
	88	struct net_device *dev;
	89	void *priv;
7b4b2fa3 FW	90	u8 pf;
7b4b2fa3 FW	91	enum nf_hook_ops_type hook_ops_type:8;
e3b37f11 AC	92	unsigned int hooknum;
	93	/* Hooks are ordered in ascending priority. */
	94	int priority;
	95	};
	96
	97	struct nf_hook_entry {
d415b9eb AC	98	nf_hookfn *hook;
d415b9eb AC	99	void *priv;
e3b37f11 AC	100	};
e3b37f11 AC	101
8c873e21 FW	102	struct nf_hook_entries_rcu_head {
	103	struct rcu_head head;
	104	void *allocation;
	105	};
	106
960632ec AC	107	struct nf_hook_entries {
	108	u16 num_hook_entries;
	109	/* padding */
	110	struct nf_hook_entry hooks[];
	111
8c873e21 FW	112	/* trailer: pointers to original orig_ops of each hook,
	113	* followed by rcu_head and scratch space used for freeing
	114	* the structure via call_rcu.
960632ec	115	*
8c873e21 FW	116	* This is not part of struct nf_hook_entry since its only
8c873e21 FW	117	* needed in slow path (hook register/unregister):
960632ec	118	* const struct nf_hook_ops *orig_ops[]
8c873e21 FW	119	*
	120	* For the same reason, we store this at end -- its
	121	* only needed when a hook is deleted, not during
	122	* packet path processing:
	123	* struct nf_hook_entries_rcu_head head
960632ec AC	124	*/
960632ec AC	125	};
0aa8c57a	126
f19438bd	127	#ifdef CONFIG_NETFILTER
960632ec	128	static inline struct nf_hook_ops *nf_hook_entries_get_hook_ops(const struct nf_hook_entries e)
0aa8c57a	129	{
960632ec AC	130	unsigned int n = e->num_hook_entries;
	131	const void *hook_end;
	132
	133	hook_end = &e->hooks[n]; /* this is past ->hooks[]! */
	134
	135	return (struct nf_hook_ops **)hook_end;
0aa8c57a AC	136	}
	137
	138	static inline int
	139	nf_hook_entry_hookfn(const struct nf_hook_entry entry, struct sk_buff skb,
	140	struct nf_hook_state *state)
	141	{
d415b9eb	142	return entry->hook(entry->priv, skb, state);
0aa8c57a AC	143	}
0aa8c57a AC	144
107a9f4d DM	145	static inline void nf_hook_state_init(struct nf_hook_state *p,
107a9f4d DM	146	unsigned int hook,
1610a73c	147	u_int8_t pf,
107a9f4d DM	148	struct net_device *indev,
107a9f4d DM	149	struct net_device *outdev,
1c984f8a	150	struct sock *sk,
b11b1f65	151	struct net *net,
0c4b51f0	152	int (okfn)(struct net , struct sock , struct sk_buff ))
107a9f4d DM	153	{
107a9f4d DM	154	p->hook = hook;
107a9f4d DM	155	p->pf = pf;
	156	p->in = indev;
	157	p->out = outdev;
1c984f8a	158	p->sk = sk;
b11b1f65	159	p->net = net;
107a9f4d DM	160	p->okfn = okfn;
	161	}
	162
1da177e4	163
1da177e4	164
d94d9fee	165	struct nf_sockopt_ops {
1da177e4 LT	166	struct list_head list;
1da177e4 LT	167
76108cea	168	u_int8_t pf;
1da177e4 LT	169
	170	/* Non-inclusive ranges: use 0/0/NULL to never get called. */
	171	int set_optmin;
	172	int set_optmax;
c2f12630 CH	173	int (set)(struct sock sk, int optval, sockptr_t arg,
c2f12630 CH	174	unsigned int len);
1da177e4 LT	175	int get_optmin;
	176	int get_optmax;
	177	int (get)(struct sock sk, int optval, void __user user, int len);
16fcec35 NH	178	/* Use the module struct to lock set/get code in place */
16fcec35 NH	179	struct module *owner;
1da177e4 LT	180	};
1da177e4 LT	181
1da177e4	182	/* Function to register/unregister hook points. */
085db2c0 EB	183	int nf_register_net_hook(struct net net, const struct nf_hook_ops ops);
	184	void nf_unregister_net_hook(struct net net, const struct nf_hook_ops ops);
	185	int nf_register_net_hooks(struct net net, const struct nf_hook_ops reg,
	186	unsigned int n);
	187	void nf_unregister_net_hooks(struct net net, const struct nf_hook_ops reg,
	188	unsigned int n);
	189
1da177e4 LT	190	/* Functions to register get/setsockopt ranges (non-inclusive). You
	191	need to check permissions yourself! */
	192	int nf_register_sockopt(struct nf_sockopt_ops *reg);
	193	void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
	194
e9666d10	195	#ifdef CONFIG_JUMP_LABEL
c5905afb	196	extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
a2d7ec58 ED	197	#endif
a2d7ec58 ED	198
01886bd9	199	int nf_hook_slow(struct sk_buff skb, struct nf_hook_state state,
960632ec	200	const struct nf_hook_entries *e, unsigned int i);
16a6677f	201
ca58fbe0 FW	202	void nf_hook_slow_list(struct list_head head, struct nf_hook_state state,
ca58fbe0 FW	203	const struct nf_hook_entries *e);
16a6677f	204	/**
1610a73c	205	* nf_hook - call a netfilter hook
b8d0aad0	206	*
16a6677f PM	207	* Returns 1 if the hook has allowed the packet to pass. The function
	208	* okfn must be invoked by the caller in this case. Any other return
	209	* value indicates the packet has been consumed by the hook.
	210	*/
1610a73c PNA	211	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	212	struct sock sk, struct sk_buff skb,
	213	struct net_device indev, struct net_device outdev,
	214	int (okfn)(struct net , struct sock , struct sk_buff ))
16a6677f	215	{
b0f38338	216	struct nf_hook_entries *hook_head = NULL;
e3b37f11	217	int ret = 1;
af4610c3	218
e9666d10	219	#ifdef CONFIG_JUMP_LABEL
af4610c3 FW	220	if (__builtin_constant_p(pf) &&
	221	__builtin_constant_p(hook) &&
	222	!static_key_false(&nf_hooks_needed[pf][hook]))
	223	return 1;
	224	#endif
	225
e3b37f11	226	rcu_read_lock();
b0f38338 FW	227	switch (pf) {
	228	case NFPROTO_IPV4:
	229	hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
	230	break;
	231	case NFPROTO_IPV6:
	232	hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
	233	break;
	234	case NFPROTO_ARP:
2a95183a	235	#ifdef CONFIG_NETFILTER_FAMILY_ARP
421c119f FW	236	if (WARN_ON_ONCE(hook >= ARRAY_SIZE(net->nf.hooks_arp)))
421c119f FW	237	break;
b0f38338	238	hook_head = rcu_dereference(net->nf.hooks_arp[hook]);
2a95183a	239	#endif
b0f38338 FW	240	break;
b0f38338 FW	241	case NFPROTO_BRIDGE:
2a95183a	242	#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
b0f38338	243	hook_head = rcu_dereference(net->nf.hooks_bridge[hook]);
2a95183a	244	#endif
b0f38338	245	break;
bb4badf3	246	#if IS_ENABLED(CONFIG_DECNET)
b0f38338 FW	247	case NFPROTO_DECNET:
	248	hook_head = rcu_dereference(net->nf.hooks_decnet[hook]);
	249	break;
bb4badf3	250	#endif
b0f38338 FW	251	default:
	252	WARN_ON_ONCE(1);
	253	break;
	254	}
	255
e3b37f11	256	if (hook_head) {
107a9f4d	257	struct nf_hook_state state;
cfdfab31	258
01886bd9	259	nf_hook_state_init(&state, hook, pf, indev, outdev,
1610a73c	260	sk, net, okfn);
fe72926b	261
960632ec	262	ret = nf_hook_slow(skb, &state, hook_head, 0);
cfdfab31	263	}
e3b37f11 AC	264	rcu_read_unlock();
	265
	266	return ret;
16a6677f PM	267	}
16a6677f PM	268
1da177e4 LT	269	/* Activate hook; either okfn or kfree_skb called, unless a hook
	270	returns NF_STOLEN (in which case, it's up to the hook to deal with
	271	the consequences).
	272
	273	Returns -ERRNO if packet dropped. Zero means queued, stolen or
	274	accepted.
	275	*/
	276
	277	/* RR:
	278	> I don't want nf_hook to return anything because people might forget
	279	> about async and trust the return value to mean "packet was ok".
	280
	281	AK:
	282	Just document it clearly, then you can expect some sense from kernel
	283	coders :)
	284	*/
	285
2249065f	286	static inline int
29a26a56	287	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
7026b1dd	288	struct sk_buff skb, struct net_device in, struct net_device *out,
0c4b51f0 EB	289	int (okfn)(struct net , struct sock , struct sk_buff ),
0c4b51f0 EB	290	bool cond)
2249065f	291	{
4bac6b18 PM	292	int ret;
	293
	294	if (!cond \|\|
1610a73c	295	((ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn)) == 1))
0c4b51f0	296	ret = okfn(net, sk, skb);
2249065f JE	297	return ret;
2249065f JE	298	}
1da177e4	299
2249065f	300	static inline int
29a26a56	301	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk, struct sk_buff *skb,
2249065f	302	struct net_device in, struct net_device out,
0c4b51f0	303	int (okfn)(struct net , struct sock , struct sk_buff ))
2249065f	304	{
1610a73c PNA	305	int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
	306	if (ret == 1)
	307	ret = okfn(net, sk, skb);
	308	return ret;
2249065f	309	}
1da177e4	310
17266ee9 EC	311	static inline void
	312	NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	313	struct list_head head, struct net_device in, struct net_device *out,
	314	int (okfn)(struct net , struct sock , struct sk_buff ))
	315	{
ca58fbe0 FW	316	struct nf_hook_entries *hook_head = NULL;
	317
	318	#ifdef CONFIG_JUMP_LABEL
	319	if (__builtin_constant_p(pf) &&
	320	__builtin_constant_p(hook) &&
	321	!static_key_false(&nf_hooks_needed[pf][hook]))
	322	return;
	323	#endif
	324
	325	rcu_read_lock();
	326	switch (pf) {
	327	case NFPROTO_IPV4:
	328	hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
	329	break;
	330	case NFPROTO_IPV6:
	331	hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
	332	break;
	333	default:
	334	WARN_ON_ONCE(1);
	335	break;
17266ee9	336	}
ca58fbe0 FW	337
	338	if (hook_head) {
	339	struct nf_hook_state state;
	340
	341	nf_hook_state_init(&state, hook, pf, in, out, sk, net, okfn);
	342
	343	nf_hook_slow_list(head, &state, hook_head);
	344	}
	345	rcu_read_unlock();
17266ee9 EC	346	}
17266ee9 EC	347
1da177e4	348	/* Call setsockopt() */
c2f12630	349	int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, sockptr_t opt,
b7058842	350	unsigned int len);
76108cea	351	int nf_getsockopt(struct sock sk, u_int8_t pf, int optval, char __user opt,
1da177e4	352	int *len);
3fdadf7d	353
1841a4c7	354	struct flowi;
02f014d8	355	struct nf_queue_entry;
c01cd429	356
ef71fe27 PNA	357	__sum16 nf_checksum(struct sk_buff *skb, unsigned int hook,
	358	unsigned int dataoff, u_int8_t protocol,
	359	unsigned short family);
422c346f	360
f7dcbe2f PNA	361	__sum16 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
	362	unsigned int dataoff, unsigned int len,
	363	u_int8_t protocol, unsigned short family);
3f87c08c PNA	364	int nf_route(struct net net, struct dst_entry dst, struct flowi fl,
3f87c08c PNA	365	bool strict, unsigned short family);
ce388f45	366	int nf_reroute(struct sk_buff skb, struct nf_queue_entry entry);
d63a6507	367
eb9c7ebe	368	#include <net/flow.h>
2c205dd3 PNA	369
	370	struct nf_conn;
	371	enum nf_nat_manip_type;
	372	struct nlattr;
368982cd	373	enum ip_conntrack_dir;
2c205dd3 PNA	374
	375	struct nf_nat_hook {
	376	int (parse_nat_setup)(struct nf_conn ct, enum nf_nat_manip_type manip,
	377	const struct nlattr *attr);
	378	void (decode_session)(struct sk_buff skb, struct flowi *fl);
368982cd PNA	379	unsigned int (manip_pkt)(struct sk_buff skb, struct nf_conn *ct,
	380	enum nf_nat_manip_type mtype,
	381	enum ip_conntrack_dir dir);
1bc91a5d	382	void (remove_nat_bysrc)(struct nf_conn ct);
2c205dd3 PNA	383	};
2c205dd3 PNA	384
285c8a7a	385	extern const struct nf_nat_hook __rcu *nf_nat_hook;
eb9c7ebe PM	386
eb9c7ebe PM	387	static inline void
76108cea	388	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
eb9c7ebe	389	{
4806e975	390	#if IS_ENABLED(CONFIG_NF_NAT)
285c8a7a	391	const struct nf_nat_hook *nat_hook;
eb9c7ebe	392
c7232c99	393	rcu_read_lock();
2c205dd3	394	nat_hook = rcu_dereference(nf_nat_hook);
155fb5c5	395	if (nat_hook && nat_hook->decode_session)
2c205dd3	396	nat_hook->decode_session(skb, fl);
c7232c99	397	rcu_read_unlock();
eb9c7ebe PM	398	#endif
	399	}
	400
1da177e4	401	#else /* !CONFIG_NETFILTER */
008027c3 AB	402	static inline int
	403	NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	404	struct sk_buff skb, struct net_device in, struct net_device *out,
	405	int (okfn)(struct net , struct sock , struct sk_buff ),
	406	bool cond)
	407	{
	408	return okfn(net, sk, skb);
	409	}
	410
	411	static inline int
	412	NF_HOOK(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	413	struct sk_buff skb, struct net_device in, struct net_device *out,
	414	int (okfn)(struct net , struct sock , struct sk_buff ))
	415	{
	416	return okfn(net, sk, skb);
	417	}
	418
17266ee9 EC	419	static inline void
	420	NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net net, struct sock sk,
	421	struct list_head head, struct net_device in, struct net_device *out,
	422	int (okfn)(struct net , struct sock , struct sk_buff ))
	423	{
	424	/* nothing to do */
	425	}
	426
29a26a56 EB	427	static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
	428	struct sock sk, struct sk_buff skb,
	429	struct net_device indev, struct net_device outdev,
0c4b51f0	430	int (okfn)(struct net , struct sock , struct sk_buff ))
f53b61d8	431	{
9c92d348	432	return 1;
f53b61d8	433	}
f53b61d8	434	struct flowi;
eb9c7ebe	435	static inline void
76108cea JE	436	nf_nat_decode_session(struct sk_buff skb, struct flowi fl, u_int8_t family)
	437	{
	438	}
1da177e4 LT	439	#endif /CONFIG_NETFILTER/
1da177e4 LT	440
25d7cbcd	441	#if IS_ENABLED(CONFIG_NF_CONNTRACK)
62da9865 DB	442	#include <linux/netfilter/nf_conntrack_zones_common.h>
62da9865 DB	443
a0f4ecf3	444	void nf_ct_attach(struct sk_buff , const struct sk_buff );
b60a6040 THJ	445	struct nf_conntrack_tuple;
	446	bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
	447	const struct sk_buff *skb);
b7bd1809 PNA	448	#else
b7bd1809 PNA	449	static inline void nf_ct_attach(struct sk_buff new, struct sk_buff skb) {}
b60a6040 THJ	450	struct nf_conntrack_tuple;
	451	static inline bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
	452	const struct sk_buff *skb)
	453	{
	454	return false;
	455	}
b7bd1809	456	#endif
9cb01766 PNA	457
9cb01766 PNA	458	struct nf_conn;
41d73ec0	459	enum ip_conntrack_info;
1f4b2439 PNA	460
1f4b2439 PNA	461	struct nf_ct_hook {
368982cd	462	int (update)(struct net net, struct sk_buff *skb);
1f4b2439	463	void (destroy)(struct nf_conntrack );
b60a6040 THJ	464	bool (get_tuple_skb)(struct nf_conntrack_tuple ,
b60a6040 THJ	465	const struct sk_buff *);
3fce1649	466	void (attach)(struct sk_buff nskb, const struct sk_buff *skb);
1f4b2439	467	};
285c8a7a	468	extern const struct nf_ct_hook __rcu *nf_ct_hook;
1f4b2439	469
9cb01766 PNA	470	struct nlattr;
9cb01766 PNA	471
a4b4766c	472	struct nfnl_ct_hook {
9cb01766	473	size_t (build_size)(const struct nf_conn ct);
b7bd1809 PNA	474	int (build)(struct sk_buff skb, struct nf_conn *ct,
	475	enum ip_conntrack_info ctinfo,
	476	u_int16_t ct_attr, u_int16_t ct_info_attr);
9cb01766	477	int (parse)(const struct nlattr attr, struct nf_conn *ct);
bd077937 PNA	478	int (attach_expect)(const struct nlattr attr, struct nf_conn *ct,
bd077937 PNA	479	u32 portid, u32 report);
8c88f87c	480	void (seq_adjust)(struct sk_buff skb, struct nf_conn *ct,
41d73ec0	481	enum ip_conntrack_info ctinfo, s32 off);
9cb01766	482	};
285c8a7a	483	extern const struct nfnl_ct_hook __rcu *nfnl_ct_hook;
5f79e0f9	484
e7c8899f FW	485	/**
	486	* nf_skb_duplicated - TEE target has sent a packet
	487	*
	488	* When a xtables target sends a packet, the OUTPUT and POSTROUTING
	489	* hooks are traversed again, i.e. nft and xtables are invoked recursively.
	490	*
	491	* This is used by xtables TEE target to prevent the duplicated skb from
	492	* being duplicated again.
	493	*/
	494	DECLARE_PER_CPU(bool, nf_skb_duplicated);
	495
1da177e4	496	#endif /__LINUX_NETFILTER_H/