Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux...
[linux/fpc-iii.git] / include / net / genetlink.h
blob8d4608ce8716360924ae68a24ffb25c0171187fc
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)
10 /**
11 * struct genl_multicast_group - generic netlink multicast group
12 * @name: name of the multicast group, names are per-family
14 struct genl_multicast_group {
15 char name[GENL_NAMSIZ];
18 struct genl_ops;
19 struct genl_info;
21 /**
22 * struct genl_family - generic netlink family
23 * @id: protocol family idenfitier
24 * @hdrsize: length of user specific header in bytes
25 * @name: name of family
26 * @version: protocol version
27 * @maxattr: maximum number of attributes supported
28 * @netnsok: set to true if the family can handle network
29 * namespaces and should be presented in all of them
30 * @parallel_ops: operations can be called in parallel and aren't
31 * synchronized by the core genetlink code
32 * @pre_doit: called before an operation's doit callback, it may
33 * do additional, common, filtering and return an error
34 * @post_doit: called after an operation's doit callback, it may
35 * undo operations done by pre_doit, for example release locks
36 * @mcast_bind: a socket bound to the given multicast group (which
37 * is given as the offset into the groups array)
38 * @mcast_unbind: a socket was unbound from the given multicast group.
39 * Note that unbind() will not be called symmetrically if the
40 * generic netlink family is removed while there are still open
41 * sockets.
42 * @attrbuf: buffer to store parsed attributes
43 * @family_list: family list
44 * @mcgrps: multicast groups used by this family (private)
45 * @n_mcgrps: number of multicast groups (private)
46 * @mcgrp_offset: starting number of multicast group IDs in this family
47 * @ops: the operations supported by this family (private)
48 * @n_ops: number of operations supported by this family (private)
50 struct genl_family {
51 unsigned int id;
52 unsigned int hdrsize;
53 char name[GENL_NAMSIZ];
54 unsigned int version;
55 unsigned int maxattr;
56 bool netnsok;
57 bool parallel_ops;
58 int (*pre_doit)(const struct genl_ops *ops,
59 struct sk_buff *skb,
60 struct genl_info *info);
61 void (*post_doit)(const struct genl_ops *ops,
62 struct sk_buff *skb,
63 struct genl_info *info);
64 int (*mcast_bind)(struct net *net, int group);
65 void (*mcast_unbind)(struct net *net, int group);
66 struct nlattr ** attrbuf; /* private */
67 const struct genl_ops * ops; /* private */
68 const struct genl_multicast_group *mcgrps; /* private */
69 unsigned int n_ops; /* private */
70 unsigned int n_mcgrps; /* private */
71 unsigned int mcgrp_offset; /* private */
72 struct list_head family_list; /* private */
73 struct module *module;
76 /**
77 * struct genl_info - receiving information
78 * @snd_seq: sending sequence number
79 * @snd_portid: netlink portid of sender
80 * @nlhdr: netlink message header
81 * @genlhdr: generic netlink message header
82 * @userhdr: user specific header
83 * @attrs: netlink attributes
84 * @_net: network namespace
85 * @user_ptr: user pointers
87 struct genl_info {
88 u32 snd_seq;
89 u32 snd_portid;
90 struct nlmsghdr * nlhdr;
91 struct genlmsghdr * genlhdr;
92 void * userhdr;
93 struct nlattr ** attrs;
94 possible_net_t _net;
95 void * user_ptr[2];
98 static inline struct net *genl_info_net(struct genl_info *info)
100 return read_pnet(&info->_net);
103 static inline void genl_info_net_set(struct genl_info *info, struct net *net)
105 write_pnet(&info->_net, net);
109 * struct genl_ops - generic netlink operations
110 * @cmd: command identifier
111 * @internal_flags: flags used by the family
112 * @flags: flags
113 * @policy: attribute validation policy
114 * @doit: standard command callback
115 * @start: start callback for dumps
116 * @dumpit: callback for dumpers
117 * @done: completion callback for dumps
118 * @ops_list: operations list
120 struct genl_ops {
121 const struct nla_policy *policy;
122 int (*doit)(struct sk_buff *skb,
123 struct genl_info *info);
124 int (*start)(struct netlink_callback *cb);
125 int (*dumpit)(struct sk_buff *skb,
126 struct netlink_callback *cb);
127 int (*done)(struct netlink_callback *cb);
128 u8 cmd;
129 u8 internal_flags;
130 u8 flags;
133 int __genl_register_family(struct genl_family *family);
135 static inline int genl_register_family(struct genl_family *family)
137 family->module = THIS_MODULE;
138 return __genl_register_family(family);
142 * genl_register_family_with_ops - register a generic netlink family with ops
143 * @family: generic netlink family
144 * @ops: operations to be registered
145 * @n_ops: number of elements to register
147 * Registers the specified family and operations from the specified table.
148 * Only one family may be registered with the same family name or identifier.
150 * The family id may equal GENL_ID_GENERATE causing an unique id to
151 * be automatically generated and assigned.
153 * Either a doit or dumpit callback must be specified for every registered
154 * operation or the function will fail. Only one operation structure per
155 * command identifier may be registered.
157 * See include/net/genetlink.h for more documenation on the operations
158 * structure.
160 * Return 0 on success or a negative error code.
162 static inline int
163 _genl_register_family_with_ops_grps(struct genl_family *family,
164 const struct genl_ops *ops, size_t n_ops,
165 const struct genl_multicast_group *mcgrps,
166 size_t n_mcgrps)
168 family->module = THIS_MODULE;
169 family->ops = ops;
170 family->n_ops = n_ops;
171 family->mcgrps = mcgrps;
172 family->n_mcgrps = n_mcgrps;
173 return __genl_register_family(family);
176 #define genl_register_family_with_ops(family, ops) \
177 _genl_register_family_with_ops_grps((family), \
178 (ops), ARRAY_SIZE(ops), \
179 NULL, 0)
180 #define genl_register_family_with_ops_groups(family, ops, grps) \
181 _genl_register_family_with_ops_grps((family), \
182 (ops), ARRAY_SIZE(ops), \
183 (grps), ARRAY_SIZE(grps))
185 int genl_unregister_family(struct genl_family *family);
186 void genl_notify(struct genl_family *family, struct sk_buff *skb,
187 struct genl_info *info, u32 group, gfp_t flags);
189 void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
190 struct genl_family *family, int flags, u8 cmd);
193 * genlmsg_nlhdr - Obtain netlink header from user specified header
194 * @user_hdr: user header as returned from genlmsg_put()
195 * @family: generic netlink family
197 * Returns pointer to netlink header.
199 static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
200 struct genl_family *family)
202 return (struct nlmsghdr *)((char *)user_hdr -
203 family->hdrsize -
204 GENL_HDRLEN -
205 NLMSG_HDRLEN);
209 * genlmsg_parse - parse attributes of a genetlink message
210 * @nlh: netlink message header
211 * @family: genetlink message family
212 * @tb: destination array with maxtype+1 elements
213 * @maxtype: maximum attribute type to be expected
214 * @policy: validation policy
215 * */
216 static inline int genlmsg_parse(const struct nlmsghdr *nlh,
217 const struct genl_family *family,
218 struct nlattr *tb[], int maxtype,
219 const struct nla_policy *policy)
221 return nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
222 policy);
226 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
227 * @cb: netlink callback structure that stores the sequence number
228 * @user_hdr: user header as returned from genlmsg_put()
229 * @family: generic netlink family
231 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
232 * simpler to use with generic netlink.
234 static inline void genl_dump_check_consistent(struct netlink_callback *cb,
235 void *user_hdr,
236 struct genl_family *family)
238 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
242 * genlmsg_put_reply - Add generic netlink header to a reply message
243 * @skb: socket buffer holding the message
244 * @info: receiver info
245 * @family: generic netlink family
246 * @flags: netlink message flags
247 * @cmd: generic netlink command
249 * Returns pointer to user specific header
251 static inline void *genlmsg_put_reply(struct sk_buff *skb,
252 struct genl_info *info,
253 struct genl_family *family,
254 int flags, u8 cmd)
256 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
257 flags, cmd);
261 * genlmsg_end - Finalize a generic netlink message
262 * @skb: socket buffer the message is stored in
263 * @hdr: user specific header
265 static inline void genlmsg_end(struct sk_buff *skb, void *hdr)
267 nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
271 * genlmsg_cancel - Cancel construction of a generic netlink message
272 * @skb: socket buffer the message is stored in
273 * @hdr: generic netlink message header
275 static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
277 if (hdr)
278 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
282 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
283 * @family: the generic netlink family
284 * @net: the net namespace
285 * @skb: netlink message as socket buffer
286 * @portid: own netlink portid to avoid sending to yourself
287 * @group: offset of multicast group in groups array
288 * @flags: allocation flags
290 static inline int genlmsg_multicast_netns(struct genl_family *family,
291 struct net *net, struct sk_buff *skb,
292 u32 portid, unsigned int group, gfp_t flags)
294 if (WARN_ON_ONCE(group >= family->n_mcgrps))
295 return -EINVAL;
296 group = family->mcgrp_offset + group;
297 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
301 * genlmsg_multicast - multicast a netlink message to the default netns
302 * @family: the generic netlink family
303 * @skb: netlink message as socket buffer
304 * @portid: own netlink portid to avoid sending to yourself
305 * @group: offset of multicast group in groups array
306 * @flags: allocation flags
308 static inline int genlmsg_multicast(struct genl_family *family,
309 struct sk_buff *skb, u32 portid,
310 unsigned int group, gfp_t flags)
312 return genlmsg_multicast_netns(family, &init_net, skb,
313 portid, group, flags);
317 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
318 * @family: the generic netlink family
319 * @skb: netlink message as socket buffer
320 * @portid: own netlink portid to avoid sending to yourself
321 * @group: offset of multicast group in groups array
322 * @flags: allocation flags
324 * This function must hold the RTNL or rcu_read_lock().
326 int genlmsg_multicast_allns(struct genl_family *family,
327 struct sk_buff *skb, u32 portid,
328 unsigned int group, gfp_t flags);
331 * genlmsg_unicast - unicast a netlink message
332 * @skb: netlink message as socket buffer
333 * @portid: netlink portid of the destination socket
335 static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
337 return nlmsg_unicast(net->genl_sock, skb, portid);
341 * genlmsg_reply - reply to a request
342 * @skb: netlink message to be sent back
343 * @info: receiver information
345 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
347 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
351 * gennlmsg_data - head of message payload
352 * @gnlh: genetlink message header
354 static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
356 return ((unsigned char *) gnlh + GENL_HDRLEN);
360 * genlmsg_len - length of message payload
361 * @gnlh: genetlink message header
363 static inline int genlmsg_len(const struct genlmsghdr *gnlh)
365 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
366 NLMSG_HDRLEN);
367 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
371 * genlmsg_msg_size - length of genetlink message not including padding
372 * @payload: length of message payload
374 static inline int genlmsg_msg_size(int payload)
376 return GENL_HDRLEN + payload;
380 * genlmsg_total_size - length of genetlink message including padding
381 * @payload: length of message payload
383 static inline int genlmsg_total_size(int payload)
385 return NLMSG_ALIGN(genlmsg_msg_size(payload));
389 * genlmsg_new - Allocate a new generic netlink message
390 * @payload: size of the message payload
391 * @flags: the type of memory to allocate.
393 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
395 return nlmsg_new(genlmsg_total_size(payload), flags);
399 * genl_set_err - report error to genetlink broadcast listeners
400 * @family: the generic netlink family
401 * @net: the network namespace to report the error to
402 * @portid: the PORTID of a process that we want to skip (if any)
403 * @group: the broadcast group that will notice the error
404 * (this is the offset of the multicast group in the groups array)
405 * @code: error code, must be negative (as usual in kernelspace)
407 * This function returns the number of broadcast listeners that have set the
408 * NETLINK_RECV_NO_ENOBUFS socket option.
410 static inline int genl_set_err(struct genl_family *family, struct net *net,
411 u32 portid, u32 group, int code)
413 if (WARN_ON_ONCE(group >= family->n_mcgrps))
414 return -EINVAL;
415 group = family->mcgrp_offset + group;
416 return netlink_set_err(net->genl_sock, portid, group, code);
419 static inline int genl_has_listeners(struct genl_family *family,
420 struct net *net, unsigned int group)
422 if (WARN_ON_ONCE(group >= family->n_mcgrps))
423 return -EINVAL;
424 group = family->mcgrp_offset + group;
425 return netlink_has_listeners(net->genl_sock, group);
427 #endif /* __NET_GENERIC_NETLINK_H */