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Thomas Graf482a8522005-11-10 02:25:56 +01001#ifndef __NET_GENERIC_NETLINK_H
2#define __NET_GENERIC_NETLINK_H
3
4#include <linux/genetlink.h>
5#include <net/netlink.h>
Johannes Berg134e6372009-07-10 09:51:34 +00006#include <net/net_namespace.h>
Thomas Graf482a8522005-11-10 02:25:56 +01007
Thomas Graf58050fc2012-06-28 03:57:45 +00008#define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN)
9
Thomas Graf482a8522005-11-10 02:25:56 +010010/**
Johannes Berg2dbba6f2007-07-18 15:47:52 -070011 * 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
17 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000018struct genl_multicast_group {
Johannes Berg2dbba6f2007-07-18 15:47:52 -070019 struct genl_family *family; /* private */
20 struct list_head list; /* private */
21 char name[GENL_NAMSIZ];
22 u32 id;
23};
24
Johannes Bergff4c92d2010-10-04 21:14:03 +020025struct genl_ops;
26struct genl_info;
27
Johannes Berg2dbba6f2007-07-18 15:47:52 -070028/**
Thomas Graf482a8522005-11-10 02:25:56 +010029 * 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
Johannes Berg134e6372009-07-10 09:51:34 +000035 * @netnsok: set to true if the family can handle network
36 * namespaces and should be presented in all of them
Johannes Bergff4c92d2010-10-04 21:14:03 +020037 * @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
Thomas Graf482a8522005-11-10 02:25:56 +010041 * @attrbuf: buffer to store parsed attributes
42 * @ops_list: list of all assigned operations
43 * @family_list: family list
Johannes Berg2dbba6f2007-07-18 15:47:52 -070044 * @mcast_groups: multicast groups list
Thomas Graf482a8522005-11-10 02:25:56 +010045 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000046struct genl_family {
Thomas Graf482a8522005-11-10 02:25:56 +010047 unsigned int id;
48 unsigned int hdrsize;
49 char name[GENL_NAMSIZ];
50 unsigned int version;
51 unsigned int maxattr;
Johannes Berg134e6372009-07-10 09:51:34 +000052 bool netnsok;
Pravin B Shelardef31172013-04-23 07:48:30 +000053 bool parallel_ops;
Johannes Bergff4c92d2010-10-04 21:14:03 +020054 int (*pre_doit)(struct genl_ops *ops,
55 struct sk_buff *skb,
56 struct genl_info *info);
57 void (*post_doit)(struct genl_ops *ops,
58 struct sk_buff *skb,
59 struct genl_info *info);
Thomas Graf482a8522005-11-10 02:25:56 +010060 struct nlattr ** attrbuf; /* private */
61 struct list_head ops_list; /* private */
62 struct list_head family_list; /* private */
Johannes Berg2dbba6f2007-07-18 15:47:52 -070063 struct list_head mcast_groups; /* private */
Pravin B Shelar33c6b1f2013-08-23 12:45:04 -070064 struct module *module;
Thomas Graf482a8522005-11-10 02:25:56 +010065};
66
Thomas Graf482a8522005-11-10 02:25:56 +010067/**
68 * struct genl_info - receiving information
69 * @snd_seq: sending sequence number
Eric W. Biederman15e47302012-09-07 20:12:54 +000070 * @snd_portid: netlink portid of sender
Thomas Graf482a8522005-11-10 02:25:56 +010071 * @nlhdr: netlink message header
72 * @genlhdr: generic netlink message header
73 * @userhdr: user specific header
74 * @attrs: netlink attributes
Johannes Bergff4c92d2010-10-04 21:14:03 +020075 * @_net: network namespace
76 * @user_ptr: user pointers
Thomas Graf482a8522005-11-10 02:25:56 +010077 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000078struct genl_info {
Thomas Graf482a8522005-11-10 02:25:56 +010079 u32 snd_seq;
Eric W. Biederman15e47302012-09-07 20:12:54 +000080 u32 snd_portid;
Thomas Graf482a8522005-11-10 02:25:56 +010081 struct nlmsghdr * nlhdr;
82 struct genlmsghdr * genlhdr;
83 void * userhdr;
84 struct nlattr ** attrs;
Johannes Berg134e6372009-07-10 09:51:34 +000085#ifdef CONFIG_NET_NS
86 struct net * _net;
87#endif
Johannes Bergff4c92d2010-10-04 21:14:03 +020088 void * user_ptr[2];
Thomas Graf482a8522005-11-10 02:25:56 +010089};
90
Johannes Berg134e6372009-07-10 09:51:34 +000091static inline struct net *genl_info_net(struct genl_info *info)
92{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000093 return read_pnet(&info->_net);
Johannes Berg134e6372009-07-10 09:51:34 +000094}
95
96static inline void genl_info_net_set(struct genl_info *info, struct net *net)
97{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000098 write_pnet(&info->_net, net);
Johannes Berg134e6372009-07-10 09:51:34 +000099}
Johannes Berg134e6372009-07-10 09:51:34 +0000100
Thomas Graf482a8522005-11-10 02:25:56 +0100101/**
102 * struct genl_ops - generic netlink operations
103 * @cmd: command identifier
Johannes Bergff4c92d2010-10-04 21:14:03 +0200104 * @internal_flags: flags used by the family
Thomas Graf482a8522005-11-10 02:25:56 +0100105 * @flags: flags
106 * @policy: attribute validation policy
107 * @doit: standard command callback
108 * @dumpit: callback for dumpers
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800109 * @done: completion callback for dumps
Thomas Graf482a8522005-11-10 02:25:56 +0100110 * @ops_list: operations list
111 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +0000112struct genl_ops {
Per Lidenb461d2f22006-01-03 14:13:29 -0800113 u8 cmd;
Johannes Bergff4c92d2010-10-04 21:14:03 +0200114 u8 internal_flags;
Thomas Graf482a8522005-11-10 02:25:56 +0100115 unsigned int flags;
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700116 const struct nla_policy *policy;
Thomas Graf482a8522005-11-10 02:25:56 +0100117 int (*doit)(struct sk_buff *skb,
118 struct genl_info *info);
119 int (*dumpit)(struct sk_buff *skb,
120 struct netlink_callback *cb);
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800121 int (*done)(struct netlink_callback *cb);
Thomas Graf482a8522005-11-10 02:25:56 +0100122 struct list_head ops_list;
123};
124
Pravin B Shelar33c6b1f2013-08-23 12:45:04 -0700125extern int __genl_register_family(struct genl_family *family);
126
127static inline int genl_register_family(struct genl_family *family)
128{
129 family->module = THIS_MODULE;
130 return __genl_register_family(family);
131}
132
133extern int __genl_register_family_with_ops(struct genl_family *family,
Michał Mirosława7b11d72009-05-21 10:34:04 +0000134 struct genl_ops *ops, size_t n_ops);
Pravin B Shelar33c6b1f2013-08-23 12:45:04 -0700135
136static inline int genl_register_family_with_ops(struct genl_family *family,
137 struct genl_ops *ops, size_t n_ops)
138{
139 family->module = THIS_MODULE;
140 return __genl_register_family_with_ops(family, ops, n_ops);
141}
142
Thomas Graf482a8522005-11-10 02:25:56 +0100143extern int genl_unregister_family(struct genl_family *family);
144extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
145extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
Johannes Berg2dbba6f2007-07-18 15:47:52 -0700146extern int genl_register_mc_group(struct genl_family *family,
147 struct genl_multicast_group *grp);
148extern void genl_unregister_mc_group(struct genl_family *family,
149 struct genl_multicast_group *grp);
Eric W. Biederman15e47302012-09-07 20:12:54 +0000150extern void genl_notify(struct sk_buff *skb, struct net *net, u32 portid,
Pravin B Shelar263ba612011-11-10 19:14:37 -0800151 u32 group, struct nlmsghdr *nlh, gfp_t flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100152
Eric W. Biederman15e47302012-09-07 20:12:54 +0000153void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
Denys Vlasenkoa46621a2012-01-30 15:22:06 -0500154 struct genl_family *family, int flags, u8 cmd);
Thomas Graf482a8522005-11-10 02:25:56 +0100155
156/**
Johannes Berg670dc282011-06-20 13:40:46 +0200157 * genlmsg_nlhdr - Obtain netlink header from user specified header
158 * @user_hdr: user header as returned from genlmsg_put()
159 * @family: generic netlink family
160 *
161 * Returns pointer to netlink header.
162 */
163static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
164 struct genl_family *family)
165{
166 return (struct nlmsghdr *)((char *)user_hdr -
167 family->hdrsize -
168 GENL_HDRLEN -
169 NLMSG_HDRLEN);
170}
171
172/**
173 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
174 * @cb: netlink callback structure that stores the sequence number
175 * @user_hdr: user header as returned from genlmsg_put()
176 * @family: generic netlink family
177 *
178 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
179 * simpler to use with generic netlink.
180 */
181static inline void genl_dump_check_consistent(struct netlink_callback *cb,
182 void *user_hdr,
183 struct genl_family *family)
184{
185 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
186}
187
188/**
Thomas Graf17c157c2006-11-14 19:46:02 -0800189 * genlmsg_put_reply - Add generic netlink header to a reply message
190 * @skb: socket buffer holding the message
191 * @info: receiver info
192 * @family: generic netlink family
193 * @flags: netlink message flags
194 * @cmd: generic netlink command
195 *
196 * Returns pointer to user specific header
197 */
198static inline void *genlmsg_put_reply(struct sk_buff *skb,
199 struct genl_info *info,
200 struct genl_family *family,
201 int flags, u8 cmd)
202{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000203 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
Thomas Graf17c157c2006-11-14 19:46:02 -0800204 flags, cmd);
205}
206
207/**
Thomas Graf482a8522005-11-10 02:25:56 +0100208 * genlmsg_end - Finalize a generic netlink message
209 * @skb: socket buffer the message is stored in
210 * @hdr: user specific header
211 */
212static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
213{
214 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
215}
216
217/**
218 * genlmsg_cancel - Cancel construction of a generic netlink message
219 * @skb: socket buffer the message is stored in
220 * @hdr: generic netlink message header
221 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700222static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
Thomas Graf482a8522005-11-10 02:25:56 +0100223{
Julia Lawall38db9e12011-01-28 05:43:40 +0000224 if (hdr)
225 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
Thomas Graf482a8522005-11-10 02:25:56 +0100226}
227
228/**
Johannes Berg134e6372009-07-10 09:51:34 +0000229 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
230 * @net: the net namespace
231 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000232 * @portid: own netlink portid to avoid sending to yourself
Johannes Berg134e6372009-07-10 09:51:34 +0000233 * @group: multicast group id
234 * @flags: allocation flags
235 */
236static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
Eric W. Biederman15e47302012-09-07 20:12:54 +0000237 u32 portid, unsigned int group, gfp_t flags)
Johannes Berg134e6372009-07-10 09:51:34 +0000238{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000239 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
Johannes Berg134e6372009-07-10 09:51:34 +0000240}
241
242/**
243 * genlmsg_multicast - multicast a netlink message to the default netns
Thomas Graf482a8522005-11-10 02:25:56 +0100244 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000245 * @portid: own netlink portid to avoid sending to yourself
Thomas Graf482a8522005-11-10 02:25:56 +0100246 * @group: multicast group id
Thomas Grafd387f6a2006-08-15 00:31:06 -0700247 * @flags: allocation flags
Thomas Graf482a8522005-11-10 02:25:56 +0100248 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000249static inline int genlmsg_multicast(struct sk_buff *skb, u32 portid,
Thomas Grafd387f6a2006-08-15 00:31:06 -0700250 unsigned int group, gfp_t flags)
Thomas Graf482a8522005-11-10 02:25:56 +0100251{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000252 return genlmsg_multicast_netns(&init_net, skb, portid, group, flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100253}
254
255/**
Johannes Berg134e6372009-07-10 09:51:34 +0000256 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
257 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000258 * @portid: own netlink portid to avoid sending to yourself
Johannes Berg134e6372009-07-10 09:51:34 +0000259 * @group: multicast group id
260 * @flags: allocation flags
261 *
262 * This function must hold the RTNL or rcu_read_lock().
263 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000264int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid,
Johannes Berg134e6372009-07-10 09:51:34 +0000265 unsigned int group, gfp_t flags);
266
267/**
Thomas Graf482a8522005-11-10 02:25:56 +0100268 * genlmsg_unicast - unicast a netlink message
269 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000270 * @portid: netlink portid of the destination socket
Thomas Graf482a8522005-11-10 02:25:56 +0100271 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000272static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
Thomas Graf482a8522005-11-10 02:25:56 +0100273{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000274 return nlmsg_unicast(net->genl_sock, skb, portid);
Thomas Graf482a8522005-11-10 02:25:56 +0100275}
276
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700277/**
Thomas Graf81878d22006-11-14 19:45:27 -0800278 * genlmsg_reply - reply to a request
279 * @skb: netlink message to be sent back
280 * @info: receiver information
281 */
282static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
283{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000284 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
Thomas Graf81878d22006-11-14 19:45:27 -0800285}
286
287/**
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700288 * gennlmsg_data - head of message payload
Justin P. Mattock70f23fd2011-05-10 10:16:21 +0200289 * @gnlh: genetlink message header
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700290 */
291static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
292{
293 return ((unsigned char *) gnlh + GENL_HDRLEN);
294}
295
296/**
297 * genlmsg_len - length of message payload
298 * @gnlh: genetlink message header
299 */
300static inline int genlmsg_len(const struct genlmsghdr *gnlh)
301{
302 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
303 NLMSG_HDRLEN);
304 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
305}
306
Balbir Singh17db9522006-09-30 23:28:51 -0700307/**
308 * genlmsg_msg_size - length of genetlink message not including padding
309 * @payload: length of message payload
310 */
311static inline int genlmsg_msg_size(int payload)
312{
313 return GENL_HDRLEN + payload;
314}
315
316/**
317 * genlmsg_total_size - length of genetlink message including padding
318 * @payload: length of message payload
319 */
320static inline int genlmsg_total_size(int payload)
321{
322 return NLMSG_ALIGN(genlmsg_msg_size(payload));
323}
324
Thomas Graf3dabc712006-11-14 19:44:52 -0800325/**
326 * genlmsg_new - Allocate a new generic netlink message
327 * @payload: size of the message payload
328 * @flags: the type of memory to allocate.
329 */
330static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
331{
332 return nlmsg_new(genlmsg_total_size(payload), flags);
333}
334
335
Thomas Graf482a8522005-11-10 02:25:56 +0100336#endif /* __NET_GENERIC_NETLINK_H */