Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NFNETLINK_H
3#define _NFNETLINK_H
4
5#include <linux/netlink.h>
6#include <linux/capability.h>
7#include <net/netlink.h>
8#include <uapi/linux/netfilter/nfnetlink.h>
9
10struct nfnl_callback {
11 int (*call)(struct net *net, struct sock *nl, struct sk_buff *skb,
12 const struct nlmsghdr *nlh,
13 const struct nlattr * const cda[],
14 struct netlink_ext_ack *extack);
15 int (*call_rcu)(struct net *net, struct sock *nl, struct sk_buff *skb,
16 const struct nlmsghdr *nlh,
17 const struct nlattr * const cda[],
18 struct netlink_ext_ack *extack);
19 int (*call_batch)(struct net *net, struct sock *nl, struct sk_buff *skb,
20 const struct nlmsghdr *nlh,
21 const struct nlattr * const cda[],
22 struct netlink_ext_ack *extack);
23 const struct nla_policy *policy; /* netlink attribute policy */
24 const u_int16_t attr_count; /* number of nlattr's */
25};
26
27struct nfnetlink_subsystem {
28 const char *name;
29 __u8 subsys_id; /* nfnetlink subsystem ID */
30 __u8 cb_count; /* number of callbacks */
31 const struct nfnl_callback *cb; /* callback for individual types */
32 int (*commit)(struct net *net, struct sk_buff *skb);
33 int (*abort)(struct net *net, struct sk_buff *skb);
34 bool (*valid_genid)(struct net *net, u32 genid);
35};
36
37int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
38int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
39
40int nfnetlink_has_listeners(struct net *net, unsigned int group);
41int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
42 unsigned int group, int echo, gfp_t flags);
43int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
44int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid,
45 int flags);
46
47static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
48{
49 return subsys << 8 | msg_type;
50}
51
52void nfnl_lock(__u8 subsys_id);
53void nfnl_unlock(__u8 subsys_id);
54#ifdef CONFIG_PROVE_LOCKING
55bool lockdep_nfnl_is_held(__u8 subsys_id);
56#else
57static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
58{
59 return true;
60}
61#endif /* CONFIG_PROVE_LOCKING */
62
63/*
64 * nfnl_dereference - fetch RCU pointer when updates are prevented by subsys mutex
65 *
66 * @p: The pointer to read, prior to dereferencing
67 * @ss: The nfnetlink subsystem ID
68 *
69 * Return the value of the specified RCU-protected pointer, but omit
70 * the READ_ONCE(), because caller holds the NFNL subsystem mutex.
71 */
72#define nfnl_dereference(p, ss) \
73 rcu_dereference_protected(p, lockdep_nfnl_is_held(ss))
74
75#define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
76 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
77
78#endif /* _NFNETLINK_H */