summaryrefslogtreecommitdiff
path: root/include/net/genetlink.h
blob: c5b96b2b81554e452630774254c1a2ae4e9a9f34 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
#ifndef __NET_GENERIC_NETLINK_H
#define __NET_GENERIC_NETLINK_H

#include <linux/genetlink.h>
#include <net/netlink.h>

/**
 * struct genl_family - generic netlink family
 * @id: protocol family idenfitier
 * @hdrsize: length of user specific header in bytes
 * @name: name of family
 * @version: protocol version
 * @maxattr: maximum number of attributes supported
 * @attrbuf: buffer to store parsed attributes
 * @ops_list: list of all assigned operations
 * @family_list: family list
 */
struct genl_family
{
	unsigned int		id;
	unsigned int		hdrsize;
	char			name[GENL_NAMSIZ];
	unsigned int		version;
	unsigned int		maxattr;
	struct module *		owner;
	struct nlattr **	attrbuf;	/* private */
	struct list_head	ops_list;	/* private */
	struct list_head	family_list;	/* private */
};

#define GENL_ADMIN_PERM		0x01

/**
 * struct genl_info - receiving information
 * @snd_seq: sending sequence number
 * @snd_pid: netlink pid of sender
 * @nlhdr: netlink message header
 * @genlhdr: generic netlink message header
 * @userhdr: user specific header
 * @attrs: netlink attributes
 */
struct genl_info
{
	u32			snd_seq;
	u32			snd_pid;
	struct nlmsghdr *	nlhdr;
	struct genlmsghdr *	genlhdr;
	void *			userhdr;
	struct nlattr **	attrs;
};

/**
 * struct genl_ops - generic netlink operations
 * @cmd: command identifier
 * @flags: flags
 * @policy: attribute validation policy
 * @doit: standard command callback
 * @dumpit: callback for dumpers
 * @ops_list: operations list
 */
struct genl_ops
{
	u8			cmd;
	unsigned int		flags;
	struct nla_policy	*policy;
	int		       (*doit)(struct sk_buff *skb,
				       struct genl_info *info);
	int		       (*dumpit)(struct sk_buff *skb,
					 struct netlink_callback *cb);
	struct list_head	ops_list;
};

extern int genl_register_family(struct genl_family *family);
extern int genl_unregister_family(struct genl_family *family);
extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);

extern struct sock *genl_sock;

/**
 * genlmsg_put - Add generic netlink header to netlink message
 * @skb: socket buffer holding the message
 * @pid: netlink pid the message is addressed to
 * @seq: sequence number (usually the one of the sender)
 * @type: netlink message type
 * @hdrlen: length of the user specific header
 * @flags netlink message flags
 * @cmd: generic netlink command
 * @version: version
 *
 * Returns pointer to user specific header
 */
static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
				int type, int hdrlen, int flags,
				u8 cmd, u8 version)
{
	struct nlmsghdr *nlh;
	struct genlmsghdr *hdr;

	nlh = nlmsg_put(skb, pid, seq, type, GENL_HDRLEN + hdrlen, flags);
	if (nlh == NULL)
		return NULL;

	hdr = nlmsg_data(nlh);
	hdr->cmd = cmd;
	hdr->version = version;
	hdr->reserved = 0;

	return (char *) hdr + GENL_HDRLEN;
}

/**
 * genlmsg_end - Finalize a generic netlink message
 * @skb: socket buffer the message is stored in
 * @hdr: user specific header
 */
static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
{
	return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
}

/**
 * genlmsg_cancel - Cancel construction of a generic netlink message
 * @skb: socket buffer the message is stored in
 * @hdr: generic netlink message header
 */
static inline int genlmsg_cancel(struct sk_buff *skb, void *hdr)
{
	return nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
}

/**
 * genlmsg_multicast - multicast a netlink message
 * @skb: netlink message as socket buffer
 * @pid: own netlink pid to avoid sending to yourself
 * @group: multicast group id
 */
static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
				    unsigned int group)
{
	return nlmsg_multicast(genl_sock, skb, pid, group);
}

/**
 * genlmsg_unicast - unicast a netlink message
 * @skb: netlink message as socket buffer
 * @pid: netlink pid of the destination socket
 */
static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid)
{
	return nlmsg_unicast(genl_sock, skb, pid);
}

#endif	/* __NET_GENERIC_NETLINK_H */