blob: 414a5e769fde98ba36f0bbe0b90505ffac2445ee [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NFNETLINK_H
#define _NFNETLINK_H
#include <linux/netlink.h>
#include <linux/capability.h>
#include <net/netlink.h>
#include <uapi/linux/netfilter/nfnetlink.h>
struct nfnl_callback {
int (*call)(struct net *net, struct sock *nl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[],
struct netlink_ext_ack *extack);
int (*call_rcu)(struct net *net, struct sock *nl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[],
struct netlink_ext_ack *extack);
int (*call_batch)(struct net *net, struct sock *nl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[],
struct netlink_ext_ack *extack);
const struct nla_policy *policy; /* netlink attribute policy */
const u_int16_t attr_count; /* number of nlattr's */
};
struct nfnetlink_subsystem {
const char *name;
__u8 subsys_id; /* nfnetlink subsystem ID */
__u8 cb_count; /* number of callbacks */
const struct nfnl_callback *cb; /* callback for individual types */
int (*commit)(struct net *net, struct sk_buff *skb);
int (*abort)(struct net *net, struct sk_buff *skb);
bool (*valid_genid)(struct net *net, u32 genid);
};
int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
int nfnetlink_has_listeners(struct net *net, unsigned int group);
int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
unsigned int group, int echo, gfp_t flags);
int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid,
int flags);
static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
{
return subsys << 8 | msg_type;
}
void nfnl_lock(__u8 subsys_id);
void nfnl_unlock(__u8 subsys_id);
#ifdef CONFIG_PROVE_LOCKING
bool lockdep_nfnl_is_held(__u8 subsys_id);
#else
static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
{
return true;
}
#endif /* CONFIG_PROVE_LOCKING */
/*
* nfnl_dereference - fetch RCU pointer when updates are prevented by subsys mutex
*
* @p: The pointer to read, prior to dereferencing
* @ss: The nfnetlink subsystem ID
*
* Return the value of the specified RCU-protected pointer, but omit
* both the smp_read_barrier_depends() and the ACCESS_ONCE(), because
* caller holds the NFNL subsystem mutex.
*/
#define nfnl_dereference(p, ss) \
rcu_dereference_protected(p, lockdep_nfnl_is_held(ss))
#define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
#endif /* _NFNETLINK_H */