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Linux kernel mirror (for testing)
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kernel
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linux
1#ifndef __NET_GENERIC_NETLINK_H
2#define __NET_GENERIC_NETLINK_H
3
4#include <linux/genetlink.h>
5#include <net/netlink.h>
6
7/**
8 * struct genl_multicast_group - generic netlink multicast group
9 * @name: name of the multicast group, names are per-family
10 * @id: multicast group ID, assigned by the core, to use with
11 * genlmsg_multicast().
12 * @list: list entry for linking
13 * @family: pointer to family, need not be set before registering
14 */
15struct genl_multicast_group
16{
17 struct genl_family *family; /* private */
18 struct list_head list; /* private */
19 char name[GENL_NAMSIZ];
20 u32 id;
21};
22
23/**
24 * struct genl_family - generic netlink family
25 * @id: protocol family idenfitier
26 * @hdrsize: length of user specific header in bytes
27 * @name: name of family
28 * @version: protocol version
29 * @maxattr: maximum number of attributes supported
30 * @attrbuf: buffer to store parsed attributes
31 * @ops_list: list of all assigned operations
32 * @family_list: family list
33 * @mcast_groups: multicast groups list
34 */
35struct genl_family
36{
37 unsigned int id;
38 unsigned int hdrsize;
39 char name[GENL_NAMSIZ];
40 unsigned int version;
41 unsigned int maxattr;
42 struct nlattr ** attrbuf; /* private */
43 struct list_head ops_list; /* private */
44 struct list_head family_list; /* private */
45 struct list_head mcast_groups; /* private */
46};
47
48/**
49 * struct genl_info - receiving information
50 * @snd_seq: sending sequence number
51 * @snd_pid: netlink pid of sender
52 * @nlhdr: netlink message header
53 * @genlhdr: generic netlink message header
54 * @userhdr: user specific header
55 * @attrs: netlink attributes
56 */
57struct genl_info
58{
59 u32 snd_seq;
60 u32 snd_pid;
61 struct nlmsghdr * nlhdr;
62 struct genlmsghdr * genlhdr;
63 void * userhdr;
64 struct nlattr ** attrs;
65};
66
67/**
68 * struct genl_ops - generic netlink operations
69 * @cmd: command identifier
70 * @flags: flags
71 * @policy: attribute validation policy
72 * @doit: standard command callback
73 * @dumpit: callback for dumpers
74 * @done: completion callback for dumps
75 * @ops_list: operations list
76 */
77struct genl_ops
78{
79 u8 cmd;
80 unsigned int flags;
81 const struct nla_policy *policy;
82 int (*doit)(struct sk_buff *skb,
83 struct genl_info *info);
84 int (*dumpit)(struct sk_buff *skb,
85 struct netlink_callback *cb);
86 int (*done)(struct netlink_callback *cb);
87 struct list_head ops_list;
88};
89
90extern int genl_register_family(struct genl_family *family);
91extern int genl_register_family_with_ops(struct genl_family *family,
92 struct genl_ops *ops, size_t n_ops);
93extern int genl_unregister_family(struct genl_family *family);
94extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
95extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
96extern int genl_register_mc_group(struct genl_family *family,
97 struct genl_multicast_group *grp);
98extern void genl_unregister_mc_group(struct genl_family *family,
99 struct genl_multicast_group *grp);
100
101extern struct sock *genl_sock;
102
103/**
104 * genlmsg_put - Add generic netlink header to netlink message
105 * @skb: socket buffer holding the message
106 * @pid: netlink pid the message is addressed to
107 * @seq: sequence number (usually the one of the sender)
108 * @family: generic netlink family
109 * @flags netlink message flags
110 * @cmd: generic netlink command
111 *
112 * Returns pointer to user specific header
113 */
114static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
115 struct genl_family *family, int flags, u8 cmd)
116{
117 struct nlmsghdr *nlh;
118 struct genlmsghdr *hdr;
119
120 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
121 family->hdrsize, flags);
122 if (nlh == NULL)
123 return NULL;
124
125 hdr = nlmsg_data(nlh);
126 hdr->cmd = cmd;
127 hdr->version = family->version;
128 hdr->reserved = 0;
129
130 return (char *) hdr + GENL_HDRLEN;
131}
132
133/**
134 * genlmsg_put_reply - Add generic netlink header to a reply message
135 * @skb: socket buffer holding the message
136 * @info: receiver info
137 * @family: generic netlink family
138 * @flags: netlink message flags
139 * @cmd: generic netlink command
140 *
141 * Returns pointer to user specific header
142 */
143static inline void *genlmsg_put_reply(struct sk_buff *skb,
144 struct genl_info *info,
145 struct genl_family *family,
146 int flags, u8 cmd)
147{
148 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family,
149 flags, cmd);
150}
151
152/**
153 * genlmsg_end - Finalize a generic netlink message
154 * @skb: socket buffer the message is stored in
155 * @hdr: user specific header
156 */
157static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
158{
159 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
160}
161
162/**
163 * genlmsg_cancel - Cancel construction of a generic netlink message
164 * @skb: socket buffer the message is stored in
165 * @hdr: generic netlink message header
166 */
167static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
168{
169 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
170}
171
172/**
173 * genlmsg_multicast - multicast a netlink message
174 * @skb: netlink message as socket buffer
175 * @pid: own netlink pid to avoid sending to yourself
176 * @group: multicast group id
177 * @flags: allocation flags
178 */
179static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
180 unsigned int group, gfp_t flags)
181{
182 return nlmsg_multicast(genl_sock, skb, pid, group, flags);
183}
184
185/**
186 * genlmsg_unicast - unicast a netlink message
187 * @skb: netlink message as socket buffer
188 * @pid: netlink pid of the destination socket
189 */
190static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid)
191{
192 return nlmsg_unicast(genl_sock, skb, pid);
193}
194
195/**
196 * genlmsg_reply - reply to a request
197 * @skb: netlink message to be sent back
198 * @info: receiver information
199 */
200static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
201{
202 return genlmsg_unicast(skb, info->snd_pid);
203}
204
205/**
206 * gennlmsg_data - head of message payload
207 * @gnlh: genetlink messsage header
208 */
209static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
210{
211 return ((unsigned char *) gnlh + GENL_HDRLEN);
212}
213
214/**
215 * genlmsg_len - length of message payload
216 * @gnlh: genetlink message header
217 */
218static inline int genlmsg_len(const struct genlmsghdr *gnlh)
219{
220 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
221 NLMSG_HDRLEN);
222 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
223}
224
225/**
226 * genlmsg_msg_size - length of genetlink message not including padding
227 * @payload: length of message payload
228 */
229static inline int genlmsg_msg_size(int payload)
230{
231 return GENL_HDRLEN + payload;
232}
233
234/**
235 * genlmsg_total_size - length of genetlink message including padding
236 * @payload: length of message payload
237 */
238static inline int genlmsg_total_size(int payload)
239{
240 return NLMSG_ALIGN(genlmsg_msg_size(payload));
241}
242
243/**
244 * genlmsg_new - Allocate a new generic netlink message
245 * @payload: size of the message payload
246 * @flags: the type of memory to allocate.
247 */
248static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
249{
250 return nlmsg_new(genlmsg_total_size(payload), flags);
251}
252
253
254#endif /* __NET_GENERIC_NETLINK_H */