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1#ifndef __NET_GENERIC_NETLINK_H
2#define __NET_GENERIC_NETLINK_H
3
4#include <linux/genetlink.h>
5#include <net/netlink.h>
6#include <net/net_namespace.h>
7
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
15 */
16struct genl_multicast_group {
17 struct genl_family *family; /* private */
18 struct list_head list; /* private */
19 char name[GENL_NAMSIZ];
20 u32 id;
21};
22
23struct genl_ops;
24struct genl_info;
25
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
43 */
44struct 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 */
61};
62
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
73 */
74struct 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];
85};
86
87static inline struct net *genl_info_net(struct genl_info *info)
88{
89 return read_pnet(&info->_net);
90}
91
92static inline void genl_info_net_set(struct genl_info *info, struct net *net)
93{
94 write_pnet(&info->_net, net);
95}
96
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
107 */
108struct 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;
119};
120
121extern int genl_register_family(struct genl_family *family);
122extern int genl_register_family_with_ops(struct genl_family *family,
123 struct genl_ops *ops, size_t n_ops);
124extern int genl_unregister_family(struct genl_family *family);
125extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
126extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
127extern int genl_register_mc_group(struct genl_family *family,
128 struct genl_multicast_group *grp);
129extern void genl_unregister_mc_group(struct genl_family *family,
130 struct genl_multicast_group *grp);
131
132/**
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
140 *
141 * Returns pointer to user specific header
142 */
143static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
144 struct genl_family *family, int flags, u8 cmd)
145{
146 struct nlmsghdr *nlh;
147 struct genlmsghdr *hdr;
148
149 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
150 family->hdrsize, flags);
151 if (nlh == NULL)
152 return NULL;
153
154 hdr = nlmsg_data(nlh);
155 hdr->cmd = cmd;
156 hdr->version = family->version;
157 hdr->reserved = 0;
158
159 return (char *) hdr + GENL_HDRLEN;
160}
161
162/**
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
166 *
167 * Returns pointer to netlink header.
168 */
169static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
170 struct genl_family *family)
171{
172 return (struct nlmsghdr *)((char *)user_hdr -
173 family->hdrsize -
174 GENL_HDRLEN -
175 NLMSG_HDRLEN);
176}
177
178/**
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
183 *
184 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
185 * simpler to use with generic netlink.
186 */
187static inline void genl_dump_check_consistent(struct netlink_callback *cb,
188 void *user_hdr,
189 struct genl_family *family)
190{
191 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
192}
193
194/**
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
201 *
202 * Returns pointer to user specific header
203 */
204static inline void *genlmsg_put_reply(struct sk_buff *skb,
205 struct genl_info *info,
206 struct genl_family *family,
207 int flags, u8 cmd)
208{
209 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family,
210 flags, cmd);
211}
212
213/**
214 * genlmsg_end - Finalize a generic netlink message
215 * @skb: socket buffer the message is stored in
216 * @hdr: user specific header
217 */
218static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
219{
220 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
221}
222
223/**
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
227 */
228static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
229{
230 if (hdr)
231 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
232}
233
234/**
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
241 */
242static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
243 u32 pid, unsigned int group, gfp_t flags)
244{
245 return nlmsg_multicast(net->genl_sock, skb, pid, group, flags);
246}
247
248/**
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
254 */
255static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
256 unsigned int group, gfp_t flags)
257{
258 return genlmsg_multicast_netns(&init_net, skb, pid, group, flags);
259}
260
261/**
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
267 *
268 * This function must hold the RTNL or rcu_read_lock().
269 */
270int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid,
271 unsigned int group, gfp_t flags);
272
273/**
274 * genlmsg_unicast - unicast a netlink message
275 * @skb: netlink message as socket buffer
276 * @pid: netlink pid of the destination socket
277 */
278static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 pid)
279{
280 return nlmsg_unicast(net->genl_sock, skb, pid);
281}
282
283/**
284 * genlmsg_reply - reply to a request
285 * @skb: netlink message to be sent back
286 * @info: receiver information
287 */
288static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
289{
290 return genlmsg_unicast(genl_info_net(info), skb, info->snd_pid);
291}
292
293/**
294 * gennlmsg_data - head of message payload
295 * @gnlh: genetlink message header
296 */
297static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
298{
299 return ((unsigned char *) gnlh + GENL_HDRLEN);
300}
301
302/**
303 * genlmsg_len - length of message payload
304 * @gnlh: genetlink message header
305 */
306static inline int genlmsg_len(const struct genlmsghdr *gnlh)
307{
308 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
309 NLMSG_HDRLEN);
310 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
311}
312
313/**
314 * genlmsg_msg_size - length of genetlink message not including padding
315 * @payload: length of message payload
316 */
317static inline int genlmsg_msg_size(int payload)
318{
319 return GENL_HDRLEN + payload;
320}
321
322/**
323 * genlmsg_total_size - length of genetlink message including padding
324 * @payload: length of message payload
325 */
326static inline int genlmsg_total_size(int payload)
327{
328 return NLMSG_ALIGN(genlmsg_msg_size(payload));
329}
330
331/**
332 * genlmsg_new - Allocate a new generic netlink message
333 * @payload: size of the message payload
334 * @flags: the type of memory to allocate.
335 */
336static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
337{
338 return nlmsg_new(genlmsg_total_size(payload), flags);
339}
340
341
342#endif /* __NET_GENERIC_NETLINK_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NET_GENERIC_NETLINK_H
3#define __NET_GENERIC_NETLINK_H
4
5#include <linux/genetlink.h>
6#include <net/netlink.h>
7#include <net/net_namespace.h>
8
9#define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN)
10
11/**
12 * struct genl_multicast_group - generic netlink multicast group
13 * @name: name of the multicast group, names are per-family
14 */
15struct genl_multicast_group {
16 char name[GENL_NAMSIZ];
17};
18
19struct genl_ops;
20struct genl_info;
21
22/**
23 * struct genl_family - generic netlink family
24 * @id: protocol family identifier (private)
25 * @hdrsize: length of user specific header in bytes
26 * @name: name of family
27 * @version: protocol version
28 * @maxattr: maximum number of attributes supported
29 * @policy: netlink policy
30 * @netnsok: set to true if the family can handle network
31 * namespaces and should be presented in all of them
32 * @parallel_ops: operations can be called in parallel and aren't
33 * synchronized by the core genetlink code
34 * @pre_doit: called before an operation's doit callback, it may
35 * do additional, common, filtering and return an error
36 * @post_doit: called after an operation's doit callback, it may
37 * undo operations done by pre_doit, for example release locks
38 * @mcast_bind: a socket bound to the given multicast group (which
39 * is given as the offset into the groups array)
40 * @mcast_unbind: a socket was unbound from the given multicast group.
41 * Note that unbind() will not be called symmetrically if the
42 * generic netlink family is removed while there are still open
43 * sockets.
44 * @attrbuf: buffer to store parsed attributes (private)
45 * @mcgrps: multicast groups used by this family
46 * @n_mcgrps: number of multicast groups
47 * @mcgrp_offset: starting number of multicast group IDs in this family
48 * (private)
49 * @ops: the operations supported by this family
50 * @n_ops: number of operations supported by this family
51 */
52struct genl_family {
53 int id; /* private */
54 unsigned int hdrsize;
55 char name[GENL_NAMSIZ];
56 unsigned int version;
57 unsigned int maxattr;
58 bool netnsok;
59 bool parallel_ops;
60 const struct nla_policy *policy;
61 int (*pre_doit)(const struct genl_ops *ops,
62 struct sk_buff *skb,
63 struct genl_info *info);
64 void (*post_doit)(const struct genl_ops *ops,
65 struct sk_buff *skb,
66 struct genl_info *info);
67 int (*mcast_bind)(struct net *net, int group);
68 void (*mcast_unbind)(struct net *net, int group);
69 struct nlattr ** attrbuf; /* private */
70 const struct genl_ops * ops;
71 const struct genl_multicast_group *mcgrps;
72 unsigned int n_ops;
73 unsigned int n_mcgrps;
74 unsigned int mcgrp_offset; /* private */
75 struct module *module;
76};
77
78struct nlattr **genl_family_attrbuf(const struct genl_family *family);
79
80/**
81 * struct genl_info - receiving information
82 * @snd_seq: sending sequence number
83 * @snd_portid: netlink portid of sender
84 * @nlhdr: netlink message header
85 * @genlhdr: generic netlink message header
86 * @userhdr: user specific header
87 * @attrs: netlink attributes
88 * @_net: network namespace
89 * @user_ptr: user pointers
90 * @extack: extended ACK report struct
91 */
92struct genl_info {
93 u32 snd_seq;
94 u32 snd_portid;
95 struct nlmsghdr * nlhdr;
96 struct genlmsghdr * genlhdr;
97 void * userhdr;
98 struct nlattr ** attrs;
99 possible_net_t _net;
100 void * user_ptr[2];
101 struct netlink_ext_ack *extack;
102};
103
104static inline struct net *genl_info_net(struct genl_info *info)
105{
106 return read_pnet(&info->_net);
107}
108
109static inline void genl_info_net_set(struct genl_info *info, struct net *net)
110{
111 write_pnet(&info->_net, net);
112}
113
114#define GENL_SET_ERR_MSG(info, msg) NL_SET_ERR_MSG((info)->extack, msg)
115
116static inline int genl_err_attr(struct genl_info *info, int err,
117 const struct nlattr *attr)
118{
119 info->extack->bad_attr = attr;
120
121 return err;
122}
123
124enum genl_validate_flags {
125 GENL_DONT_VALIDATE_STRICT = BIT(0),
126 GENL_DONT_VALIDATE_DUMP = BIT(1),
127 GENL_DONT_VALIDATE_DUMP_STRICT = BIT(2),
128};
129
130/**
131 * struct genl_ops - generic netlink operations
132 * @cmd: command identifier
133 * @internal_flags: flags used by the family
134 * @flags: flags
135 * @doit: standard command callback
136 * @start: start callback for dumps
137 * @dumpit: callback for dumpers
138 * @done: completion callback for dumps
139 */
140struct genl_ops {
141 int (*doit)(struct sk_buff *skb,
142 struct genl_info *info);
143 int (*start)(struct netlink_callback *cb);
144 int (*dumpit)(struct sk_buff *skb,
145 struct netlink_callback *cb);
146 int (*done)(struct netlink_callback *cb);
147 u8 cmd;
148 u8 internal_flags;
149 u8 flags;
150 u8 validate;
151};
152
153int genl_register_family(struct genl_family *family);
154int genl_unregister_family(const struct genl_family *family);
155void genl_notify(const struct genl_family *family, struct sk_buff *skb,
156 struct genl_info *info, u32 group, gfp_t flags);
157
158void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
159 const struct genl_family *family, int flags, u8 cmd);
160
161/**
162 * genlmsg_nlhdr - Obtain netlink header from user specified header
163 * @user_hdr: user header as returned from genlmsg_put()
164 *
165 * Returns pointer to netlink header.
166 */
167static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr)
168{
169 return (struct nlmsghdr *)((char *)user_hdr -
170 GENL_HDRLEN -
171 NLMSG_HDRLEN);
172}
173
174/**
175 * genlmsg_parse_deprecated - parse attributes of a genetlink message
176 * @nlh: netlink message header
177 * @family: genetlink message family
178 * @tb: destination array with maxtype+1 elements
179 * @maxtype: maximum attribute type to be expected
180 * @policy: validation policy
181 * @extack: extended ACK report struct
182 */
183static inline int genlmsg_parse_deprecated(const struct nlmsghdr *nlh,
184 const struct genl_family *family,
185 struct nlattr *tb[], int maxtype,
186 const struct nla_policy *policy,
187 struct netlink_ext_ack *extack)
188{
189 return __nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
190 policy, NL_VALIDATE_LIBERAL, extack);
191}
192
193/**
194 * genlmsg_parse - parse attributes of a genetlink message
195 * @nlh: netlink message header
196 * @family: genetlink message family
197 * @tb: destination array with maxtype+1 elements
198 * @maxtype: maximum attribute type to be expected
199 * @policy: validation policy
200 * @extack: extended ACK report struct
201 */
202static inline int genlmsg_parse(const struct nlmsghdr *nlh,
203 const struct genl_family *family,
204 struct nlattr *tb[], int maxtype,
205 const struct nla_policy *policy,
206 struct netlink_ext_ack *extack)
207{
208 return __nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
209 policy, NL_VALIDATE_STRICT, extack);
210}
211
212/**
213 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
214 * @cb: netlink callback structure that stores the sequence number
215 * @user_hdr: user header as returned from genlmsg_put()
216 *
217 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
218 * simpler to use with generic netlink.
219 */
220static inline void genl_dump_check_consistent(struct netlink_callback *cb,
221 void *user_hdr)
222{
223 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr));
224}
225
226/**
227 * genlmsg_put_reply - Add generic netlink header to a reply message
228 * @skb: socket buffer holding the message
229 * @info: receiver info
230 * @family: generic netlink family
231 * @flags: netlink message flags
232 * @cmd: generic netlink command
233 *
234 * Returns pointer to user specific header
235 */
236static inline void *genlmsg_put_reply(struct sk_buff *skb,
237 struct genl_info *info,
238 const struct genl_family *family,
239 int flags, u8 cmd)
240{
241 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
242 flags, cmd);
243}
244
245/**
246 * genlmsg_end - Finalize a generic netlink message
247 * @skb: socket buffer the message is stored in
248 * @hdr: user specific header
249 */
250static inline void genlmsg_end(struct sk_buff *skb, void *hdr)
251{
252 nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
253}
254
255/**
256 * genlmsg_cancel - Cancel construction of a generic netlink message
257 * @skb: socket buffer the message is stored in
258 * @hdr: generic netlink message header
259 */
260static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
261{
262 if (hdr)
263 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
264}
265
266/**
267 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
268 * @family: the generic netlink family
269 * @net: the net namespace
270 * @skb: netlink message as socket buffer
271 * @portid: own netlink portid to avoid sending to yourself
272 * @group: offset of multicast group in groups array
273 * @flags: allocation flags
274 */
275static inline int genlmsg_multicast_netns(const struct genl_family *family,
276 struct net *net, struct sk_buff *skb,
277 u32 portid, unsigned int group, gfp_t flags)
278{
279 if (WARN_ON_ONCE(group >= family->n_mcgrps))
280 return -EINVAL;
281 group = family->mcgrp_offset + group;
282 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
283}
284
285/**
286 * genlmsg_multicast - multicast a netlink message to the default netns
287 * @family: the generic netlink family
288 * @skb: netlink message as socket buffer
289 * @portid: own netlink portid to avoid sending to yourself
290 * @group: offset of multicast group in groups array
291 * @flags: allocation flags
292 */
293static inline int genlmsg_multicast(const struct genl_family *family,
294 struct sk_buff *skb, u32 portid,
295 unsigned int group, gfp_t flags)
296{
297 return genlmsg_multicast_netns(family, &init_net, skb,
298 portid, group, flags);
299}
300
301/**
302 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
303 * @family: the generic netlink family
304 * @skb: netlink message as socket buffer
305 * @portid: own netlink portid to avoid sending to yourself
306 * @group: offset of multicast group in groups array
307 * @flags: allocation flags
308 *
309 * This function must hold the RTNL or rcu_read_lock().
310 */
311int genlmsg_multicast_allns(const struct genl_family *family,
312 struct sk_buff *skb, u32 portid,
313 unsigned int group, gfp_t flags);
314
315/**
316 * genlmsg_unicast - unicast a netlink message
317 * @skb: netlink message as socket buffer
318 * @portid: netlink portid of the destination socket
319 */
320static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
321{
322 return nlmsg_unicast(net->genl_sock, skb, portid);
323}
324
325/**
326 * genlmsg_reply - reply to a request
327 * @skb: netlink message to be sent back
328 * @info: receiver information
329 */
330static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
331{
332 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
333}
334
335/**
336 * gennlmsg_data - head of message payload
337 * @gnlh: genetlink message header
338 */
339static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
340{
341 return ((unsigned char *) gnlh + GENL_HDRLEN);
342}
343
344/**
345 * genlmsg_len - length of message payload
346 * @gnlh: genetlink message header
347 */
348static inline int genlmsg_len(const struct genlmsghdr *gnlh)
349{
350 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
351 NLMSG_HDRLEN);
352 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
353}
354
355/**
356 * genlmsg_msg_size - length of genetlink message not including padding
357 * @payload: length of message payload
358 */
359static inline int genlmsg_msg_size(int payload)
360{
361 return GENL_HDRLEN + payload;
362}
363
364/**
365 * genlmsg_total_size - length of genetlink message including padding
366 * @payload: length of message payload
367 */
368static inline int genlmsg_total_size(int payload)
369{
370 return NLMSG_ALIGN(genlmsg_msg_size(payload));
371}
372
373/**
374 * genlmsg_new - Allocate a new generic netlink message
375 * @payload: size of the message payload
376 * @flags: the type of memory to allocate.
377 */
378static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
379{
380 return nlmsg_new(genlmsg_total_size(payload), flags);
381}
382
383/**
384 * genl_set_err - report error to genetlink broadcast listeners
385 * @family: the generic netlink family
386 * @net: the network namespace to report the error to
387 * @portid: the PORTID of a process that we want to skip (if any)
388 * @group: the broadcast group that will notice the error
389 * (this is the offset of the multicast group in the groups array)
390 * @code: error code, must be negative (as usual in kernelspace)
391 *
392 * This function returns the number of broadcast listeners that have set the
393 * NETLINK_RECV_NO_ENOBUFS socket option.
394 */
395static inline int genl_set_err(const struct genl_family *family,
396 struct net *net, u32 portid,
397 u32 group, int code)
398{
399 if (WARN_ON_ONCE(group >= family->n_mcgrps))
400 return -EINVAL;
401 group = family->mcgrp_offset + group;
402 return netlink_set_err(net->genl_sock, portid, group, code);
403}
404
405static inline int genl_has_listeners(const struct genl_family *family,
406 struct net *net, unsigned int group)
407{
408 if (WARN_ON_ONCE(group >= family->n_mcgrps))
409 return -EINVAL;
410 group = family->mcgrp_offset + group;
411 return netlink_has_listeners(net->genl_sock, group);
412}
413#endif /* __NET_GENERIC_NETLINK_H */