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[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / net / genetlink.h
blob82d8d09faa44d4adeb108e127d2a22696a761b83
1 #ifndef __NET_GENERIC_NETLINK_H
2 #define __NET_GENERIC_NETLINK_H
4 #include <linux/genetlink.h>
5 #include <net/netlink.h>
6 #include <net/net_namespace.h>
8 /**
9 * struct genl_multicast_group - generic netlink multicast group
10 * @name: name of the multicast group, names are per-family
11 * @id: multicast group ID, assigned by the core, to use with
12 * genlmsg_multicast().
13 * @list: list entry for linking
14 * @family: pointer to family, need not be set before registering
16 struct genl_multicast_group {
17 struct genl_family *family; /* private */
18 struct list_head list; /* private */
19 char name[GENL_NAMSIZ];
20 u32 id;
23 struct genl_ops;
24 struct genl_info;
26 /**
27 * struct genl_family - generic netlink family
28 * @id: protocol family idenfitier
29 * @hdrsize: length of user specific header in bytes
30 * @name: name of family
31 * @version: protocol version
32 * @maxattr: maximum number of attributes supported
33 * @netnsok: set to true if the family can handle network
34 * namespaces and should be presented in all of them
35 * @pre_doit: called before an operation's doit callback, it may
36 * do additional, common, filtering and return an error
37 * @post_doit: called after an operation's doit callback, it may
38 * undo operations done by pre_doit, for example release locks
39 * @attrbuf: buffer to store parsed attributes
40 * @ops_list: list of all assigned operations
41 * @family_list: family list
42 * @mcast_groups: multicast groups list
44 struct genl_family {
45 unsigned int id;
46 unsigned int hdrsize;
47 char name[GENL_NAMSIZ];
48 unsigned int version;
49 unsigned int maxattr;
50 bool netnsok;
51 int (*pre_doit)(struct genl_ops *ops,
52 struct sk_buff *skb,
53 struct genl_info *info);
54 void (*post_doit)(struct genl_ops *ops,
55 struct sk_buff *skb,
56 struct genl_info *info);
57 struct nlattr ** attrbuf; /* private */
58 struct list_head ops_list; /* private */
59 struct list_head family_list; /* private */
60 struct list_head mcast_groups; /* private */
63 /**
64 * struct genl_info - receiving information
65 * @snd_seq: sending sequence number
66 * @snd_pid: netlink pid of sender
67 * @nlhdr: netlink message header
68 * @genlhdr: generic netlink message header
69 * @userhdr: user specific header
70 * @attrs: netlink attributes
71 * @_net: network namespace
72 * @user_ptr: user pointers
74 struct genl_info {
75 u32 snd_seq;
76 u32 snd_pid;
77 struct nlmsghdr * nlhdr;
78 struct genlmsghdr * genlhdr;
79 void * userhdr;
80 struct nlattr ** attrs;
81 #ifdef CONFIG_NET_NS
82 struct net * _net;
83 #endif
84 void * user_ptr[2];
87 static inline struct net *genl_info_net(struct genl_info *info)
89 return read_pnet(&info->_net);
92 static inline void genl_info_net_set(struct genl_info *info, struct net *net)
94 write_pnet(&info->_net, net);
97 /**
98 * struct genl_ops - generic netlink operations
99 * @cmd: command identifier
100 * @internal_flags: flags used by the family
101 * @flags: flags
102 * @policy: attribute validation policy
103 * @doit: standard command callback
104 * @dumpit: callback for dumpers
105 * @done: completion callback for dumps
106 * @ops_list: operations list
108 struct genl_ops {
109 u8 cmd;
110 u8 internal_flags;
111 unsigned int flags;
112 const struct nla_policy *policy;
113 int (*doit)(struct sk_buff *skb,
114 struct genl_info *info);
115 int (*dumpit)(struct sk_buff *skb,
116 struct netlink_callback *cb);
117 int (*done)(struct netlink_callback *cb);
118 struct list_head ops_list;
121 extern int genl_register_family(struct genl_family *family);
122 extern int genl_register_family_with_ops(struct genl_family *family,
123 struct genl_ops *ops, size_t n_ops);
124 extern int genl_unregister_family(struct genl_family *family);
125 extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
126 extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
127 extern int genl_register_mc_group(struct genl_family *family,
128 struct genl_multicast_group *grp);
129 extern void genl_unregister_mc_group(struct genl_family *family,
130 struct genl_multicast_group *grp);
133 * genlmsg_put - Add generic netlink header to netlink message
134 * @skb: socket buffer holding the message
135 * @pid: netlink pid the message is addressed to
136 * @seq: sequence number (usually the one of the sender)
137 * @family: generic netlink family
138 * @flags netlink message flags
139 * @cmd: generic netlink command
141 * Returns pointer to user specific header
143 static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
144 struct genl_family *family, int flags, u8 cmd)
146 struct nlmsghdr *nlh;
147 struct genlmsghdr *hdr;
149 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
150 family->hdrsize, flags);
151 if (nlh == NULL)
152 return NULL;
154 hdr = nlmsg_data(nlh);
155 hdr->cmd = cmd;
156 hdr->version = family->version;
157 hdr->reserved = 0;
159 return (char *) hdr + GENL_HDRLEN;
163 * genlmsg_nlhdr - Obtain netlink header from user specified header
164 * @user_hdr: user header as returned from genlmsg_put()
165 * @family: generic netlink family
167 * Returns pointer to netlink header.
169 static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
170 struct genl_family *family)
172 return (struct nlmsghdr *)((char *)user_hdr -
173 family->hdrsize -
174 GENL_HDRLEN -
175 NLMSG_HDRLEN);
179 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
180 * @cb: netlink callback structure that stores the sequence number
181 * @user_hdr: user header as returned from genlmsg_put()
182 * @family: generic netlink family
184 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
185 * simpler to use with generic netlink.
187 static inline void genl_dump_check_consistent(struct netlink_callback *cb,
188 void *user_hdr,
189 struct genl_family *family)
191 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
195 * genlmsg_put_reply - Add generic netlink header to a reply message
196 * @skb: socket buffer holding the message
197 * @info: receiver info
198 * @family: generic netlink family
199 * @flags: netlink message flags
200 * @cmd: generic netlink command
202 * Returns pointer to user specific header
204 static inline void *genlmsg_put_reply(struct sk_buff *skb,
205 struct genl_info *info,
206 struct genl_family *family,
207 int flags, u8 cmd)
209 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family,
210 flags, cmd);
214 * genlmsg_end - Finalize a generic netlink message
215 * @skb: socket buffer the message is stored in
216 * @hdr: user specific header
218 static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
220 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
224 * genlmsg_cancel - Cancel construction of a generic netlink message
225 * @skb: socket buffer the message is stored in
226 * @hdr: generic netlink message header
228 static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
230 if (hdr)
231 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
235 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
236 * @net: the net namespace
237 * @skb: netlink message as socket buffer
238 * @pid: own netlink pid to avoid sending to yourself
239 * @group: multicast group id
240 * @flags: allocation flags
242 static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
243 u32 pid, unsigned int group, gfp_t flags)
245 return nlmsg_multicast(net->genl_sock, skb, pid, group, flags);
249 * genlmsg_multicast - multicast a netlink message to the default netns
250 * @skb: netlink message as socket buffer
251 * @pid: own netlink pid to avoid sending to yourself
252 * @group: multicast group id
253 * @flags: allocation flags
255 static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
256 unsigned int group, gfp_t flags)
258 return genlmsg_multicast_netns(&init_net, skb, pid, group, flags);
262 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
263 * @skb: netlink message as socket buffer
264 * @pid: own netlink pid to avoid sending to yourself
265 * @group: multicast group id
266 * @flags: allocation flags
268 * This function must hold the RTNL or rcu_read_lock().
270 int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid,
271 unsigned int group, gfp_t flags);
274 * genlmsg_unicast - unicast a netlink message
275 * @skb: netlink message as socket buffer
276 * @pid: netlink pid of the destination socket
278 static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 pid)
280 return nlmsg_unicast(net->genl_sock, skb, pid);
284 * genlmsg_reply - reply to a request
285 * @skb: netlink message to be sent back
286 * @info: receiver information
288 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
290 return genlmsg_unicast(genl_info_net(info), skb, info->snd_pid);
294 * gennlmsg_data - head of message payload
295 * @gnlh: genetlink message header
297 static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
299 return ((unsigned char *) gnlh + GENL_HDRLEN);
303 * genlmsg_len - length of message payload
304 * @gnlh: genetlink message header
306 static inline int genlmsg_len(const struct genlmsghdr *gnlh)
308 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
309 NLMSG_HDRLEN);
310 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
314 * genlmsg_msg_size - length of genetlink message not including padding
315 * @payload: length of message payload
317 static inline int genlmsg_msg_size(int payload)
319 return GENL_HDRLEN + payload;
323 * genlmsg_total_size - length of genetlink message including padding
324 * @payload: length of message payload
326 static inline int genlmsg_total_size(int payload)
328 return NLMSG_ALIGN(genlmsg_msg_size(payload));
332 * genlmsg_new - Allocate a new generic netlink message
333 * @payload: size of the message payload
334 * @flags: the type of memory to allocate.
336 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
338 return nlmsg_new(genlmsg_total_size(payload), flags);
342 #endif /* __NET_GENERIC_NETLINK_H */