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
10 struct 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
27 enum nfnl_abort_action {
28 NFNL_ABORT_NONE = 0,
29 NFNL_ABORT_AUTOLOAD,
30 NFNL_ABORT_VALIDATE,
31 };
32
33 struct nfnetlink_subsystem {
34 const char *name;
35 __u8 subsys_id; /* nfnetlink subsystem ID */
36 __u8 cb_count; /* number of callbacks */
37 const struct nfnl_callback *cb; /* callback for individual types */
38 struct module *owner;
39 int (*commit)(struct net *net, struct sk_buff *skb);
40 int (*abort)(struct net *net, struct sk_buff *skb,
41 enum nfnl_abort_action action);
42 bool (*valid_genid)(struct net *net, u32 genid);
43 };
44
45 int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
46 int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
47
48 int nfnetlink_has_listeners(struct net *net, unsigned int group);
49 int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
50 unsigned int group, int echo, gfp_t flags);
51 int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
52 int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid);
53
nfnl_msg_type(u8 subsys,u8 msg_type)54 static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
55 {
56 return subsys << 8 | msg_type;
57 }
58
nfnl_fill_hdr(struct nlmsghdr * nlh,u8 family,u8 version,__be16 res_id)59 static inline void nfnl_fill_hdr(struct nlmsghdr *nlh, u8 family, u8 version,
60 __be16 res_id)
61 {
62 struct nfgenmsg *nfmsg;
63
64 nfmsg = nlmsg_data(nlh);
65 nfmsg->nfgen_family = family;
66 nfmsg->version = version;
67 nfmsg->res_id = res_id;
68 }
69
nfnl_msg_put(struct sk_buff * skb,u32 portid,u32 seq,int type,int flags,u8 family,u8 version,__be16 res_id)70 static inline struct nlmsghdr *nfnl_msg_put(struct sk_buff *skb, u32 portid,
71 u32 seq, int type, int flags,
72 u8 family, u8 version,
73 __be16 res_id)
74 {
75 struct nlmsghdr *nlh;
76
77 nlh = nlmsg_put(skb, portid, seq, type, sizeof(struct nfgenmsg), flags);
78 if (!nlh)
79 return NULL;
80
81 nfnl_fill_hdr(nlh, family, version, res_id);
82
83 return nlh;
84 }
85
86 void nfnl_lock(__u8 subsys_id);
87 void nfnl_unlock(__u8 subsys_id);
88 #ifdef CONFIG_PROVE_LOCKING
89 bool lockdep_nfnl_is_held(__u8 subsys_id);
90 #else
lockdep_nfnl_is_held(__u8 subsys_id)91 static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
92 {
93 return true;
94 }
95 #endif /* CONFIG_PROVE_LOCKING */
96
97 #define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
98 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
99
100 #endif /* _NFNETLINK_H */
101