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_info {
11 struct net *net;
12 struct sock *sk;
13 const struct nlmsghdr *nlh;
14 const struct nfgenmsg *nfmsg;
15 struct netlink_ext_ack *extack;
16};
17
18enum nfnl_callback_type {
19 NFNL_CB_UNSPEC = 0,
20 NFNL_CB_MUTEX,
21 NFNL_CB_RCU,
22 NFNL_CB_BATCH,
23};
24
25struct nfnl_callback {
26 int (*call)(struct sk_buff *skb, const struct nfnl_info *info,
27 const struct nlattr * const cda[]);
28 const struct nla_policy *policy;
29 enum nfnl_callback_type type;
30 __u16 attr_count;
31};
32
33enum nfnl_abort_action {
34 NFNL_ABORT_NONE = 0,
35 NFNL_ABORT_AUTOLOAD,
36 NFNL_ABORT_VALIDATE,
37};
38
39struct nfnetlink_subsystem {
40 const char *name;
41 __u8 subsys_id; /* nfnetlink subsystem ID */
42 __u8 cb_count; /* number of callbacks */
43 const struct nfnl_callback *cb; /* callback for individual types */
44 struct module *owner;
45 int (*commit)(struct net *net, struct sk_buff *skb);
46 int (*abort)(struct net *net, struct sk_buff *skb,
47 enum nfnl_abort_action action);
48 bool (*valid_genid)(struct net *net, u32 genid);
49};
50
51int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
52int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
53
54int nfnetlink_has_listeners(struct net *net, unsigned int group);
55int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
56 unsigned int group, int echo, gfp_t flags);
57int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
58int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid);
59void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid,
60 __u32 group, gfp_t allocation);
61
62static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
63{
64 return subsys << 8 | msg_type;
65}
66
67static inline void nfnl_fill_hdr(struct nlmsghdr *nlh, u8 family, u8 version,
68 __be16 res_id)
69{
70 struct nfgenmsg *nfmsg;
71
72 nfmsg = nlmsg_data(nlh);
73 nfmsg->nfgen_family = family;
74 nfmsg->version = version;
75 nfmsg->res_id = res_id;
76}
77
78static inline struct nlmsghdr *nfnl_msg_put(struct sk_buff *skb, u32 portid,
79 u32 seq, int type, int flags,
80 u8 family, u8 version,
81 __be16 res_id)
82{
83 struct nlmsghdr *nlh;
84
85 nlh = nlmsg_put(skb, portid, seq, type, payload: sizeof(struct nfgenmsg), flags);
86 if (!nlh)
87 return NULL;
88
89 nfnl_fill_hdr(nlh, family, version, res_id);
90
91 return nlh;
92}
93
94void nfnl_lock(__u8 subsys_id);
95void nfnl_unlock(__u8 subsys_id);
96#ifdef CONFIG_PROVE_LOCKING
97bool lockdep_nfnl_is_held(__u8 subsys_id);
98#else
99static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
100{
101 return true;
102}
103#endif /* CONFIG_PROVE_LOCKING */
104
105#define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
106 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
107
108#endif /* _NFNETLINK_H */
109