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 #define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN)
11 * struct genl_multicast_group - generic netlink multicast group
12 * @name: name of the multicast group, names are per-family
13 * @id: multicast group ID, assigned by the core, to use with
14 * genlmsg_multicast().
15 * @list: list entry for linking
16 * @family: pointer to family, need not be set before registering
18 struct genl_multicast_group {
19 struct genl_family *family; /* private */
20 struct list_head list; /* private */
21 char name[GENL_NAMSIZ];
29 * struct genl_family - generic netlink family
30 * @id: protocol family idenfitier
31 * @hdrsize: length of user specific header in bytes
32 * @name: name of family
33 * @version: protocol version
34 * @maxattr: maximum number of attributes supported
35 * @netnsok: set to true if the family can handle network
36 * namespaces and should be presented in all of them
37 * @pre_doit: called before an operation's doit callback, it may
38 * do additional, common, filtering and return an error
39 * @post_doit: called after an operation's doit callback, it may
40 * undo operations done by pre_doit, for example release locks
41 * @attrbuf: buffer to store parsed attributes
42 * @family_list: family list
43 * @mcast_groups: multicast groups list
44 * @ops: the operations supported by this family (private)
45 * @n_ops: number of operations supported by this family (private)
50 char name[GENL_NAMSIZ];
55 int (*pre_doit)(const struct genl_ops *ops,
57 struct genl_info *info);
58 void (*post_doit)(const struct genl_ops *ops,
60 struct genl_info *info);
61 struct nlattr ** attrbuf; /* private */
62 const struct genl_ops * ops; /* private */
63 unsigned int n_ops; /* private */
64 struct list_head family_list; /* private */
65 struct list_head mcast_groups; /* private */
66 struct module *module;
70 * struct genl_info - receiving information
71 * @snd_seq: sending sequence number
72 * @snd_portid: netlink portid of sender
73 * @nlhdr: netlink message header
74 * @genlhdr: generic netlink message header
75 * @userhdr: user specific header
76 * @attrs: netlink attributes
77 * @_net: network namespace
78 * @user_ptr: user pointers
83 struct nlmsghdr * nlhdr;
84 struct genlmsghdr * genlhdr;
86 struct nlattr ** attrs;
93 static inline struct net *genl_info_net(struct genl_info *info)
95 return read_pnet(&info->_net);
98 static inline void genl_info_net_set(struct genl_info *info, struct net *net)
100 write_pnet(&info->_net, net);
104 * struct genl_ops - generic netlink operations
105 * @cmd: command identifier
106 * @internal_flags: flags used by the family
108 * @policy: attribute validation policy
109 * @doit: standard command callback
110 * @dumpit: callback for dumpers
111 * @done: completion callback for dumps
112 * @ops_list: operations list
115 const struct nla_policy *policy;
116 int (*doit)(struct sk_buff *skb,
117 struct genl_info *info);
118 int (*dumpit)(struct sk_buff *skb,
119 struct netlink_callback *cb);
120 int (*done)(struct netlink_callback *cb);
126 int __genl_register_family(struct genl_family *family);
128 static inline int genl_register_family(struct genl_family *family)
130 family->module = THIS_MODULE;
131 return __genl_register_family(family);
135 * genl_register_family_with_ops - register a generic netlink family with ops
136 * @family: generic netlink family
137 * @ops: operations to be registered
138 * @n_ops: number of elements to register
140 * Registers the specified family and operations from the specified table.
141 * Only one family may be registered with the same family name or identifier.
143 * The family id may equal GENL_ID_GENERATE causing an unique id to
144 * be automatically generated and assigned.
146 * Either a doit or dumpit callback must be specified for every registered
147 * operation or the function will fail. Only one operation structure per
148 * command identifier may be registered.
150 * See include/net/genetlink.h for more documenation on the operations
153 * Return 0 on success or a negative error code.
155 static inline int _genl_register_family_with_ops(struct genl_family *family,
156 const struct genl_ops *ops,
159 family->module = THIS_MODULE;
161 family->n_ops = n_ops;
162 return __genl_register_family(family);
165 #define genl_register_family_with_ops(family, ops) \
166 _genl_register_family_with_ops((family), (ops), ARRAY_SIZE(ops))
168 int genl_unregister_family(struct genl_family *family);
169 int genl_register_mc_group(struct genl_family *family,
170 struct genl_multicast_group *grp);
171 void genl_unregister_mc_group(struct genl_family *family,
172 struct genl_multicast_group *grp);
173 void genl_notify(struct sk_buff *skb, struct net *net, u32 portid,
174 u32 group, struct nlmsghdr *nlh, gfp_t flags);
176 void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
177 struct genl_family *family, int flags, u8 cmd);
180 * genlmsg_nlhdr - Obtain netlink header from user specified header
181 * @user_hdr: user header as returned from genlmsg_put()
182 * @family: generic netlink family
184 * Returns pointer to netlink header.
186 static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
187 struct genl_family *family)
189 return (struct nlmsghdr *)((char *)user_hdr -
196 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
197 * @cb: netlink callback structure that stores the sequence number
198 * @user_hdr: user header as returned from genlmsg_put()
199 * @family: generic netlink family
201 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
202 * simpler to use with generic netlink.
204 static inline void genl_dump_check_consistent(struct netlink_callback *cb,
206 struct genl_family *family)
208 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
212 * genlmsg_put_reply - Add generic netlink header to a reply message
213 * @skb: socket buffer holding the message
214 * @info: receiver info
215 * @family: generic netlink family
216 * @flags: netlink message flags
217 * @cmd: generic netlink command
219 * Returns pointer to user specific header
221 static inline void *genlmsg_put_reply(struct sk_buff *skb,
222 struct genl_info *info,
223 struct genl_family *family,
226 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
231 * genlmsg_end - Finalize a generic netlink message
232 * @skb: socket buffer the message is stored in
233 * @hdr: user specific header
235 static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
237 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
241 * genlmsg_cancel - Cancel construction of a generic netlink message
242 * @skb: socket buffer the message is stored in
243 * @hdr: generic netlink message header
245 static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
248 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
252 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
253 * @net: the net namespace
254 * @skb: netlink message as socket buffer
255 * @portid: own netlink portid to avoid sending to yourself
256 * @group: multicast group id
257 * @flags: allocation flags
259 static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
260 u32 portid, unsigned int group, gfp_t flags)
262 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
266 * genlmsg_multicast - multicast a netlink message to the default netns
267 * @skb: netlink message as socket buffer
268 * @portid: own netlink portid to avoid sending to yourself
269 * @group: multicast group id
270 * @flags: allocation flags
272 static inline int genlmsg_multicast(struct sk_buff *skb, u32 portid,
273 unsigned int group, gfp_t flags)
275 return genlmsg_multicast_netns(&init_net, skb, portid, group, flags);
279 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
280 * @skb: netlink message as socket buffer
281 * @portid: own netlink portid to avoid sending to yourself
282 * @group: multicast group id
283 * @flags: allocation flags
285 * This function must hold the RTNL or rcu_read_lock().
287 int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid,
288 unsigned int group, gfp_t flags);
291 * genlmsg_unicast - unicast a netlink message
292 * @skb: netlink message as socket buffer
293 * @portid: netlink portid of the destination socket
295 static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
297 return nlmsg_unicast(net->genl_sock, skb, portid);
301 * genlmsg_reply - reply to a request
302 * @skb: netlink message to be sent back
303 * @info: receiver information
305 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
307 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
311 * gennlmsg_data - head of message payload
312 * @gnlh: genetlink message header
314 static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
316 return ((unsigned char *) gnlh + GENL_HDRLEN);
320 * genlmsg_len - length of message payload
321 * @gnlh: genetlink message header
323 static inline int genlmsg_len(const struct genlmsghdr *gnlh)
325 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
327 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
331 * genlmsg_msg_size - length of genetlink message not including padding
332 * @payload: length of message payload
334 static inline int genlmsg_msg_size(int payload)
336 return GENL_HDRLEN + payload;
340 * genlmsg_total_size - length of genetlink message including padding
341 * @payload: length of message payload
343 static inline int genlmsg_total_size(int payload)
345 return NLMSG_ALIGN(genlmsg_msg_size(payload));
349 * genlmsg_new - Allocate a new generic netlink message
350 * @payload: size of the message payload
351 * @flags: the type of memory to allocate.
353 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
355 return nlmsg_new(genlmsg_total_size(payload), flags);
359 #endif /* __NET_GENERIC_NETLINK_H */