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 <linux/android_kabi.h>
8 #include <net/netlink.h>
9 #include <uapi/linux/netfilter/nfnetlink.h>
10
11 struct nfnl_callback {
12 int (*call)(struct net *net, struct sock *nl, struct sk_buff *skb,
13 const struct nlmsghdr *nlh,
14 const struct nlattr * const cda[],
15 struct netlink_ext_ack *extack);
16 int (*call_rcu)(struct net *net, struct sock *nl, struct sk_buff *skb,
17 const struct nlmsghdr *nlh,
18 const struct nlattr * const cda[],
19 struct netlink_ext_ack *extack);
20 int (*call_batch)(struct net *net, struct sock *nl, struct sk_buff *skb,
21 const struct nlmsghdr *nlh,
22 const struct nlattr * const cda[],
23 struct netlink_ext_ack *extack);
24 const struct nla_policy *policy; /* netlink attribute policy */
25 const u_int16_t attr_count; /* number of nlattr's */
26
27 ANDROID_KABI_RESERVE(1);
28 };
29
30 enum nfnl_abort_action {
31 NFNL_ABORT_NONE = 0,
32 NFNL_ABORT_AUTOLOAD,
33 NFNL_ABORT_VALIDATE,
34 };
35
36 struct nfnetlink_subsystem {
37 const char *name;
38 __u8 subsys_id; /* nfnetlink subsystem ID */
39 __u8 cb_count; /* number of callbacks */
40 const struct nfnl_callback *cb; /* callback for individual types */
41 struct module *owner;
42 int (*commit)(struct net *net, struct sk_buff *skb);
43 int (*abort)(struct net *net, struct sk_buff *skb,
44 enum nfnl_abort_action action);
45 void (*cleanup)(struct net *net);
46 bool (*valid_genid)(struct net *net, u32 genid);
47
48 ANDROID_KABI_RESERVE(1);
49 };
50
51 int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n);
52 int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n);
53
54 int nfnetlink_has_listeners(struct net *net, unsigned int group);
55 int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
56 unsigned int group, int echo, gfp_t flags);
57 int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error);
58 int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid);
59
nfnl_msg_type(u8 subsys,u8 msg_type)60 static inline u16 nfnl_msg_type(u8 subsys, u8 msg_type)
61 {
62 return subsys << 8 | msg_type;
63 }
64
nfnl_fill_hdr(struct nlmsghdr * nlh,u8 family,u8 version,__be16 res_id)65 static inline void nfnl_fill_hdr(struct nlmsghdr *nlh, u8 family, u8 version,
66 __be16 res_id)
67 {
68 struct nfgenmsg *nfmsg;
69
70 nfmsg = nlmsg_data(nlh);
71 nfmsg->nfgen_family = family;
72 nfmsg->version = version;
73 nfmsg->res_id = res_id;
74 }
75
nfnl_msg_put(struct sk_buff * skb,u32 portid,u32 seq,int type,int flags,u8 family,u8 version,__be16 res_id)76 static inline struct nlmsghdr *nfnl_msg_put(struct sk_buff *skb, u32 portid,
77 u32 seq, int type, int flags,
78 u8 family, u8 version,
79 __be16 res_id)
80 {
81 struct nlmsghdr *nlh;
82
83 nlh = nlmsg_put(skb, portid, seq, type, sizeof(struct nfgenmsg), flags);
84 if (!nlh)
85 return NULL;
86
87 nfnl_fill_hdr(nlh, family, version, res_id);
88
89 return nlh;
90 }
91
92 void nfnl_lock(__u8 subsys_id);
93 void nfnl_unlock(__u8 subsys_id);
94 #ifdef CONFIG_PROVE_LOCKING
95 bool lockdep_nfnl_is_held(__u8 subsys_id);
96 #else
lockdep_nfnl_is_held(__u8 subsys_id)97 static inline bool lockdep_nfnl_is_held(__u8 subsys_id)
98 {
99 return true;
100 }
101 #endif /* CONFIG_PROVE_LOCKING */
102
103 #define MODULE_ALIAS_NFNL_SUBSYS(subsys) \
104 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys))
105
106 #endif /* _NFNETLINK_H */
107