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
118 const struct nla_policy *policy;
119 int (*doit)(struct sk_buff *skb,
120 struct genl_info *info);
121 int (*dumpit)(struct sk_buff *skb,
122 struct netlink_callback *cb);
123 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);
134 int __genl_register_family_with_ops(struct genl_family *family,
135 const struct genl_ops *ops, size_t n_ops);
137 static inline int genl_register_family_with_ops(struct genl_family *family,
138 const struct genl_ops *ops, size_t n_ops)
140 family->module = THIS_MODULE;
141 return __genl_register_family_with_ops(family, ops, n_ops);
144 int genl_unregister_family(struct genl_family *family);
145 int genl_register_mc_group(struct genl_family *family,
146 struct genl_multicast_group *grp);
147 void genl_unregister_mc_group(struct genl_family *family,
148 struct genl_multicast_group *grp);
149 void genl_notify(struct sk_buff *skb, struct net *net, u32 portid,
150 u32 group, struct nlmsghdr *nlh, gfp_t flags);
152 void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
153 struct genl_family *family, int flags, u8 cmd);
156 * genlmsg_nlhdr - Obtain netlink header from user specified header
157 * @user_hdr: user header as returned from genlmsg_put()
158 * @family: generic netlink family
160 * Returns pointer to netlink header.
162 static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
163 struct genl_family *family)
165 return (struct nlmsghdr *)((char *)user_hdr -
172 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
173 * @cb: netlink callback structure that stores the sequence number
174 * @user_hdr: user header as returned from genlmsg_put()
175 * @family: generic netlink family
177 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
178 * simpler to use with generic netlink.
180 static inline void genl_dump_check_consistent(struct netlink_callback *cb,
182 struct genl_family *family)
184 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
188 * genlmsg_put_reply - Add generic netlink header to a reply message
189 * @skb: socket buffer holding the message
190 * @info: receiver info
191 * @family: generic netlink family
192 * @flags: netlink message flags
193 * @cmd: generic netlink command
195 * Returns pointer to user specific header
197 static inline void *genlmsg_put_reply(struct sk_buff *skb,
198 struct genl_info *info,
199 struct genl_family *family,
202 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
207 * genlmsg_end - Finalize a generic netlink message
208 * @skb: socket buffer the message is stored in
209 * @hdr: user specific header
211 static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
213 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
217 * genlmsg_cancel - Cancel construction of a generic netlink message
218 * @skb: socket buffer the message is stored in
219 * @hdr: generic netlink message header
221 static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
224 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
228 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
229 * @net: the net namespace
230 * @skb: netlink message as socket buffer
231 * @portid: own netlink portid to avoid sending to yourself
232 * @group: multicast group id
233 * @flags: allocation flags
235 static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
236 u32 portid, unsigned int group, gfp_t flags)
238 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
242 * genlmsg_multicast - multicast a netlink message to the default netns
243 * @skb: netlink message as socket buffer
244 * @portid: own netlink portid to avoid sending to yourself
245 * @group: multicast group id
246 * @flags: allocation flags
248 static inline int genlmsg_multicast(struct sk_buff *skb, u32 portid,
249 unsigned int group, gfp_t flags)
251 return genlmsg_multicast_netns(&init_net, skb, portid, group, flags);
255 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
256 * @skb: netlink message as socket buffer
257 * @portid: own netlink portid to avoid sending to yourself
258 * @group: multicast group id
259 * @flags: allocation flags
261 * This function must hold the RTNL or rcu_read_lock().
263 int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid,
264 unsigned int group, gfp_t flags);
267 * genlmsg_unicast - unicast a netlink message
268 * @skb: netlink message as socket buffer
269 * @portid: netlink portid of the destination socket
271 static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
273 return nlmsg_unicast(net->genl_sock, skb, portid);
277 * genlmsg_reply - reply to a request
278 * @skb: netlink message to be sent back
279 * @info: receiver information
281 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
283 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
287 * gennlmsg_data - head of message payload
288 * @gnlh: genetlink message header
290 static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
292 return ((unsigned char *) gnlh + GENL_HDRLEN);
296 * genlmsg_len - length of message payload
297 * @gnlh: genetlink message header
299 static inline int genlmsg_len(const struct genlmsghdr *gnlh)
301 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
303 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
307 * genlmsg_msg_size - length of genetlink message not including padding
308 * @payload: length of message payload
310 static inline int genlmsg_msg_size(int payload)
312 return GENL_HDRLEN + payload;
316 * genlmsg_total_size - length of genetlink message including padding
317 * @payload: length of message payload
319 static inline int genlmsg_total_size(int payload)
321 return NLMSG_ALIGN(genlmsg_msg_size(payload));
325 * genlmsg_new - Allocate a new generic netlink message
326 * @payload: size of the message payload
327 * @flags: the type of memory to allocate.
329 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
331 return nlmsg_new(genlmsg_total_size(payload), flags);
335 #endif /* __NET_GENERIC_NETLINK_H */