1
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
13
14
15struct genl_multicast_group {
16 char name[GENL_NAMSIZ];
17};
18
19struct genl_ops;
20struct genl_info;
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51struct genl_family {
52 int id;
53 unsigned int hdrsize;
54 char name[GENL_NAMSIZ];
55 unsigned int version;
56 unsigned int maxattr;
57 bool netnsok;
58 bool parallel_ops;
59 int (*pre_doit)(const struct genl_ops *ops,
60 struct sk_buff *skb,
61 struct genl_info *info);
62 void (*post_doit)(const struct genl_ops *ops,
63 struct sk_buff *skb,
64 struct genl_info *info);
65 int (*mcast_bind)(struct net *net, int group);
66 void (*mcast_unbind)(struct net *net, int group);
67 struct nlattr ** attrbuf;
68 const struct genl_ops * ops;
69 const struct genl_multicast_group *mcgrps;
70 unsigned int n_ops;
71 unsigned int n_mcgrps;
72 unsigned int mcgrp_offset;
73 struct module *module;
74};
75
76struct nlattr **genl_family_attrbuf(const struct genl_family *family);
77
78
79
80
81
82
83
84
85
86
87
88
89
90struct genl_info {
91 u32 snd_seq;
92 u32 snd_portid;
93 struct nlmsghdr * nlhdr;
94 struct genlmsghdr * genlhdr;
95 void * userhdr;
96 struct nlattr ** attrs;
97 possible_net_t _net;
98 void * user_ptr[2];
99 struct netlink_ext_ack *extack;
100};
101
102static inline struct net *genl_info_net(struct genl_info *info)
103{
104 return read_pnet(&info->_net);
105}
106
107static inline void genl_info_net_set(struct genl_info *info, struct net *net)
108{
109 write_pnet(&info->_net, net);
110}
111
112#define GENL_SET_ERR_MSG(info, msg) NL_SET_ERR_MSG((info)->extack, msg)
113
114static inline int genl_err_attr(struct genl_info *info, int err,
115 struct nlattr *attr)
116{
117 info->extack->bad_attr = attr;
118
119 return err;
120}
121
122
123
124
125
126
127
128
129
130
131
132
133struct genl_ops {
134 const struct nla_policy *policy;
135 int (*doit)(struct sk_buff *skb,
136 struct genl_info *info);
137 int (*start)(struct netlink_callback *cb);
138 int (*dumpit)(struct sk_buff *skb,
139 struct netlink_callback *cb);
140 int (*done)(struct netlink_callback *cb);
141 u8 cmd;
142 u8 internal_flags;
143 u8 flags;
144};
145
146int genl_register_family(struct genl_family *family);
147int genl_unregister_family(const struct genl_family *family);
148void genl_notify(const struct genl_family *family, struct sk_buff *skb,
149 struct genl_info *info, u32 group, gfp_t flags);
150
151void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
152 const struct genl_family *family, int flags, u8 cmd);
153
154
155
156
157
158
159
160
161static inline struct nlmsghdr *
162genlmsg_nlhdr(void *user_hdr, const struct genl_family *family)
163{
164 return (struct nlmsghdr *)((char *)user_hdr -
165 family->hdrsize -
166 GENL_HDRLEN -
167 NLMSG_HDRLEN);
168}
169
170
171
172
173
174
175
176
177
178
179static inline int genlmsg_parse(const struct nlmsghdr *nlh,
180 const struct genl_family *family,
181 struct nlattr *tb[], int maxtype,
182 const struct nla_policy *policy,
183 struct netlink_ext_ack *extack)
184{
185 return nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
186 policy, extack);
187}
188
189
190
191
192
193
194
195
196
197
198static inline void genl_dump_check_consistent(struct netlink_callback *cb,
199 void *user_hdr,
200 const struct genl_family *family)
201{
202 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
203}
204
205
206
207
208
209
210
211
212
213
214
215static inline void *genlmsg_put_reply(struct sk_buff *skb,
216 struct genl_info *info,
217 const struct genl_family *family,
218 int flags, u8 cmd)
219{
220 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
221 flags, cmd);
222}
223
224
225
226
227
228
229static inline void genlmsg_end(struct sk_buff *skb, void *hdr)
230{
231 nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
232}
233
234
235
236
237
238
239static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
240{
241 if (hdr)
242 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
243}
244
245
246
247
248
249
250
251
252
253
254static inline int genlmsg_multicast_netns(const struct genl_family *family,
255 struct net *net, struct sk_buff *skb,
256 u32 portid, unsigned int group, gfp_t flags)
257{
258 if (WARN_ON_ONCE(group >= family->n_mcgrps))
259 return -EINVAL;
260 group = family->mcgrp_offset + group;
261 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
262}
263
264
265
266
267
268
269
270
271
272static inline int genlmsg_multicast(const struct genl_family *family,
273 struct sk_buff *skb, u32 portid,
274 unsigned int group, gfp_t flags)
275{
276 return genlmsg_multicast_netns(family, &init_net, skb,
277 portid, group, flags);
278}
279
280
281
282
283
284
285
286
287
288
289
290int genlmsg_multicast_allns(const struct genl_family *family,
291 struct sk_buff *skb, u32 portid,
292 unsigned int group, gfp_t flags);
293
294
295
296
297
298
299static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
300{
301 return nlmsg_unicast(net->genl_sock, skb, portid);
302}
303
304
305
306
307
308
309static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
310{
311 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
312}
313
314
315
316
317
318static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
319{
320 return ((unsigned char *) gnlh + GENL_HDRLEN);
321}
322
323
324
325
326
327static inline int genlmsg_len(const struct genlmsghdr *gnlh)
328{
329 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
330 NLMSG_HDRLEN);
331 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
332}
333
334
335
336
337
338static inline int genlmsg_msg_size(int payload)
339{
340 return GENL_HDRLEN + payload;
341}
342
343
344
345
346
347static inline int genlmsg_total_size(int payload)
348{
349 return NLMSG_ALIGN(genlmsg_msg_size(payload));
350}
351
352
353
354
355
356
357static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
358{
359 return nlmsg_new(genlmsg_total_size(payload), flags);
360}
361
362
363
364
365
366
367
368
369
370
371
372
373
374static inline int genl_set_err(const struct genl_family *family,
375 struct net *net, u32 portid,
376 u32 group, int code)
377{
378 if (WARN_ON_ONCE(group >= family->n_mcgrps))
379 return -EINVAL;
380 group = family->mcgrp_offset + group;
381 return netlink_set_err(net->genl_sock, portid, group, code);
382}
383
384static inline int genl_has_listeners(const struct genl_family *family,
385 struct net *net, unsigned int group)
386{
387 if (WARN_ON_ONCE(group >= family->n_mcgrps))
388 return -EINVAL;
389 group = family->mcgrp_offset + group;
390 return netlink_has_listeners(net->genl_sock, group);
391}
392#endif
393