blob: bdfbe68c1c3b271bf20b2ef23d5d0325bda2f906 [file] [log] [blame]
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;
Johannes Bergff4c92d2010-10-04 21:14:03 +020053 int (*pre_doit)(struct genl_ops *ops,
54 struct sk_buff *skb,
55 struct genl_info *info);
56 void (*post_doit)(struct genl_ops *ops,
57 struct sk_buff *skb,
58 struct genl_info *info);
Thomas Graf482a8522005-11-10 02:25:56 +010059 struct nlattr ** attrbuf; /* private */
60 struct list_head ops_list; /* private */
61 struct list_head family_list; /* private */
Johannes Berg2dbba6f2007-07-18 15:47:52 -070062 struct list_head mcast_groups; /* private */
Thomas Graf482a8522005-11-10 02:25:56 +010063};
64
Thomas Graf482a8522005-11-10 02:25:56 +010065/**
66 * struct genl_info - receiving information
67 * @snd_seq: sending sequence number
Eric W. Biederman15e47302012-09-07 20:12:54 +000068 * @snd_portid: netlink portid of sender
Thomas Graf482a8522005-11-10 02:25:56 +010069 * @nlhdr: netlink message header
70 * @genlhdr: generic netlink message header
71 * @userhdr: user specific header
72 * @attrs: netlink attributes
Johannes Bergff4c92d2010-10-04 21:14:03 +020073 * @_net: network namespace
74 * @user_ptr: user pointers
Thomas Graf482a8522005-11-10 02:25:56 +010075 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000076struct genl_info {
Thomas Graf482a8522005-11-10 02:25:56 +010077 u32 snd_seq;
Eric W. Biederman15e47302012-09-07 20:12:54 +000078 u32 snd_portid;
Thomas Graf482a8522005-11-10 02:25:56 +010079 struct nlmsghdr * nlhdr;
80 struct genlmsghdr * genlhdr;
81 void * userhdr;
82 struct nlattr ** attrs;
Johannes Berg134e6372009-07-10 09:51:34 +000083#ifdef CONFIG_NET_NS
84 struct net * _net;
85#endif
Johannes Bergff4c92d2010-10-04 21:14:03 +020086 void * user_ptr[2];
Thomas Graf482a8522005-11-10 02:25:56 +010087};
88
Johannes Berg134e6372009-07-10 09:51:34 +000089static inline struct net *genl_info_net(struct genl_info *info)
90{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000091 return read_pnet(&info->_net);
Johannes Berg134e6372009-07-10 09:51:34 +000092}
93
94static inline void genl_info_net_set(struct genl_info *info, struct net *net)
95{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000096 write_pnet(&info->_net, net);
Johannes Berg134e6372009-07-10 09:51:34 +000097}
Johannes Berg134e6372009-07-10 09:51:34 +000098
Thomas Graf482a8522005-11-10 02:25:56 +010099/**
100 * struct genl_ops - generic netlink operations
101 * @cmd: command identifier
Johannes Bergff4c92d2010-10-04 21:14:03 +0200102 * @internal_flags: flags used by the family
Thomas Graf482a8522005-11-10 02:25:56 +0100103 * @flags: flags
104 * @policy: attribute validation policy
105 * @doit: standard command callback
106 * @dumpit: callback for dumpers
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800107 * @done: completion callback for dumps
Thomas Graf482a8522005-11-10 02:25:56 +0100108 * @ops_list: operations list
109 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +0000110struct genl_ops {
Per Lidenb461d2f22006-01-03 14:13:29 -0800111 u8 cmd;
Johannes Bergff4c92d2010-10-04 21:14:03 +0200112 u8 internal_flags;
Thomas Graf482a8522005-11-10 02:25:56 +0100113 unsigned int flags;
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700114 const struct nla_policy *policy;
Thomas Graf482a8522005-11-10 02:25:56 +0100115 int (*doit)(struct sk_buff *skb,
116 struct genl_info *info);
117 int (*dumpit)(struct sk_buff *skb,
118 struct netlink_callback *cb);
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800119 int (*done)(struct netlink_callback *cb);
Thomas Graf482a8522005-11-10 02:25:56 +0100120 struct list_head ops_list;
121};
122
123extern int genl_register_family(struct genl_family *family);
Michał Mirosława7b11d72009-05-21 10:34:04 +0000124extern int genl_register_family_with_ops(struct genl_family *family,
125 struct genl_ops *ops, size_t n_ops);
Thomas Graf482a8522005-11-10 02:25:56 +0100126extern int genl_unregister_family(struct genl_family *family);
127extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
128extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
Johannes Berg2dbba6f2007-07-18 15:47:52 -0700129extern int genl_register_mc_group(struct genl_family *family,
130 struct genl_multicast_group *grp);
131extern void genl_unregister_mc_group(struct genl_family *family,
132 struct genl_multicast_group *grp);
Eric W. Biederman15e47302012-09-07 20:12:54 +0000133extern void genl_notify(struct sk_buff *skb, struct net *net, u32 portid,
Pravin B Shelar263ba612011-11-10 19:14:37 -0800134 u32 group, struct nlmsghdr *nlh, gfp_t flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100135
Eric W. Biederman15e47302012-09-07 20:12:54 +0000136void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
Denys Vlasenkoa46621a2012-01-30 15:22:06 -0500137 struct genl_family *family, int flags, u8 cmd);
Thomas Graf482a8522005-11-10 02:25:56 +0100138
139/**
Johannes Berg670dc282011-06-20 13:40:46 +0200140 * genlmsg_nlhdr - Obtain netlink header from user specified header
141 * @user_hdr: user header as returned from genlmsg_put()
142 * @family: generic netlink family
143 *
144 * Returns pointer to netlink header.
145 */
146static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
147 struct genl_family *family)
148{
149 return (struct nlmsghdr *)((char *)user_hdr -
150 family->hdrsize -
151 GENL_HDRLEN -
152 NLMSG_HDRLEN);
153}
154
155/**
156 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
157 * @cb: netlink callback structure that stores the sequence number
158 * @user_hdr: user header as returned from genlmsg_put()
159 * @family: generic netlink family
160 *
161 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
162 * simpler to use with generic netlink.
163 */
164static inline void genl_dump_check_consistent(struct netlink_callback *cb,
165 void *user_hdr,
166 struct genl_family *family)
167{
168 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
169}
170
171/**
Thomas Graf17c157c2006-11-14 19:46:02 -0800172 * genlmsg_put_reply - Add generic netlink header to a reply message
173 * @skb: socket buffer holding the message
174 * @info: receiver info
175 * @family: generic netlink family
176 * @flags: netlink message flags
177 * @cmd: generic netlink command
178 *
179 * Returns pointer to user specific header
180 */
181static inline void *genlmsg_put_reply(struct sk_buff *skb,
182 struct genl_info *info,
183 struct genl_family *family,
184 int flags, u8 cmd)
185{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000186 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
Thomas Graf17c157c2006-11-14 19:46:02 -0800187 flags, cmd);
188}
189
190/**
Thomas Graf482a8522005-11-10 02:25:56 +0100191 * genlmsg_end - Finalize a generic netlink message
192 * @skb: socket buffer the message is stored in
193 * @hdr: user specific header
194 */
195static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
196{
197 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
198}
199
200/**
201 * genlmsg_cancel - Cancel construction of a generic netlink message
202 * @skb: socket buffer the message is stored in
203 * @hdr: generic netlink message header
204 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700205static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
Thomas Graf482a8522005-11-10 02:25:56 +0100206{
Julia Lawall38db9e12011-01-28 05:43:40 +0000207 if (hdr)
208 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
Thomas Graf482a8522005-11-10 02:25:56 +0100209}
210
211/**
Johannes Berg134e6372009-07-10 09:51:34 +0000212 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
213 * @net: the net namespace
214 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000215 * @portid: own netlink portid to avoid sending to yourself
Johannes Berg134e6372009-07-10 09:51:34 +0000216 * @group: multicast group id
217 * @flags: allocation flags
218 */
219static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
Eric W. Biederman15e47302012-09-07 20:12:54 +0000220 u32 portid, unsigned int group, gfp_t flags)
Johannes Berg134e6372009-07-10 09:51:34 +0000221{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000222 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
Johannes Berg134e6372009-07-10 09:51:34 +0000223}
224
225/**
226 * genlmsg_multicast - multicast a netlink message to the default netns
Thomas Graf482a8522005-11-10 02:25:56 +0100227 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000228 * @portid: own netlink portid to avoid sending to yourself
Thomas Graf482a8522005-11-10 02:25:56 +0100229 * @group: multicast group id
Thomas Grafd387f6a2006-08-15 00:31:06 -0700230 * @flags: allocation flags
Thomas Graf482a8522005-11-10 02:25:56 +0100231 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000232static inline int genlmsg_multicast(struct sk_buff *skb, u32 portid,
Thomas Grafd387f6a2006-08-15 00:31:06 -0700233 unsigned int group, gfp_t flags)
Thomas Graf482a8522005-11-10 02:25:56 +0100234{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000235 return genlmsg_multicast_netns(&init_net, skb, portid, group, flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100236}
237
238/**
Johannes Berg134e6372009-07-10 09:51:34 +0000239 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
240 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000241 * @portid: own netlink portid to avoid sending to yourself
Johannes Berg134e6372009-07-10 09:51:34 +0000242 * @group: multicast group id
243 * @flags: allocation flags
244 *
245 * This function must hold the RTNL or rcu_read_lock().
246 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000247int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid,
Johannes Berg134e6372009-07-10 09:51:34 +0000248 unsigned int group, gfp_t flags);
249
250/**
Thomas Graf482a8522005-11-10 02:25:56 +0100251 * genlmsg_unicast - unicast a netlink message
252 * @skb: netlink message as socket buffer
Eric W. Biederman15e47302012-09-07 20:12:54 +0000253 * @portid: netlink portid of the destination socket
Thomas Graf482a8522005-11-10 02:25:56 +0100254 */
Eric W. Biederman15e47302012-09-07 20:12:54 +0000255static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
Thomas Graf482a8522005-11-10 02:25:56 +0100256{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000257 return nlmsg_unicast(net->genl_sock, skb, portid);
Thomas Graf482a8522005-11-10 02:25:56 +0100258}
259
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700260/**
Thomas Graf81878d22006-11-14 19:45:27 -0800261 * genlmsg_reply - reply to a request
262 * @skb: netlink message to be sent back
263 * @info: receiver information
264 */
265static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
266{
Eric W. Biederman15e47302012-09-07 20:12:54 +0000267 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
Thomas Graf81878d22006-11-14 19:45:27 -0800268}
269
270/**
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700271 * gennlmsg_data - head of message payload
Justin P. Mattock70f23fd2011-05-10 10:16:21 +0200272 * @gnlh: genetlink message header
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700273 */
274static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
275{
276 return ((unsigned char *) gnlh + GENL_HDRLEN);
277}
278
279/**
280 * genlmsg_len - length of message payload
281 * @gnlh: genetlink message header
282 */
283static inline int genlmsg_len(const struct genlmsghdr *gnlh)
284{
285 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
286 NLMSG_HDRLEN);
287 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
288}
289
Balbir Singh17db9522006-09-30 23:28:51 -0700290/**
291 * genlmsg_msg_size - length of genetlink message not including padding
292 * @payload: length of message payload
293 */
294static inline int genlmsg_msg_size(int payload)
295{
296 return GENL_HDRLEN + payload;
297}
298
299/**
300 * genlmsg_total_size - length of genetlink message including padding
301 * @payload: length of message payload
302 */
303static inline int genlmsg_total_size(int payload)
304{
305 return NLMSG_ALIGN(genlmsg_msg_size(payload));
306}
307
Thomas Graf3dabc712006-11-14 19:44:52 -0800308/**
309 * genlmsg_new - Allocate a new generic netlink message
310 * @payload: size of the message payload
311 * @flags: the type of memory to allocate.
312 */
313static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
314{
315 return nlmsg_new(genlmsg_total_size(payload), flags);
316}
317
318
Thomas Graf482a8522005-11-10 02:25:56 +0100319#endif /* __NET_GENERIC_NETLINK_H */