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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
8/**
Johannes Berg2dbba6f2007-07-18 15:47:52 -07009 * 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 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000016struct genl_multicast_group {
Johannes Berg2dbba6f2007-07-18 15:47:52 -070017 struct genl_family *family; /* private */
18 struct list_head list; /* private */
19 char name[GENL_NAMSIZ];
20 u32 id;
21};
22
Johannes Bergff4c92d2010-10-04 21:14:03 +020023struct genl_ops;
24struct genl_info;
25
Johannes Berg2dbba6f2007-07-18 15:47:52 -070026/**
Thomas Graf482a8522005-11-10 02:25:56 +010027 * 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
Johannes Berg134e6372009-07-10 09:51:34 +000033 * @netnsok: set to true if the family can handle network
34 * namespaces and should be presented in all of them
Johannes Bergff4c92d2010-10-04 21:14:03 +020035 * @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
Thomas Graf482a8522005-11-10 02:25:56 +010039 * @attrbuf: buffer to store parsed attributes
40 * @ops_list: list of all assigned operations
41 * @family_list: family list
Johannes Berg2dbba6f2007-07-18 15:47:52 -070042 * @mcast_groups: multicast groups list
Thomas Graf482a8522005-11-10 02:25:56 +010043 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000044struct genl_family {
Thomas Graf482a8522005-11-10 02:25:56 +010045 unsigned int id;
46 unsigned int hdrsize;
47 char name[GENL_NAMSIZ];
48 unsigned int version;
49 unsigned int maxattr;
Johannes Berg134e6372009-07-10 09:51:34 +000050 bool netnsok;
Johannes Bergff4c92d2010-10-04 21:14:03 +020051 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);
Thomas Graf482a8522005-11-10 02:25:56 +010057 struct nlattr ** attrbuf; /* private */
58 struct list_head ops_list; /* private */
59 struct list_head family_list; /* private */
Johannes Berg2dbba6f2007-07-18 15:47:52 -070060 struct list_head mcast_groups; /* private */
Thomas Graf482a8522005-11-10 02:25:56 +010061};
62
Thomas Graf482a8522005-11-10 02:25:56 +010063/**
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
Johannes Bergff4c92d2010-10-04 21:14:03 +020071 * @_net: network namespace
72 * @user_ptr: user pointers
Thomas Graf482a8522005-11-10 02:25:56 +010073 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000074struct genl_info {
Thomas Graf482a8522005-11-10 02:25:56 +010075 u32 snd_seq;
76 u32 snd_pid;
77 struct nlmsghdr * nlhdr;
78 struct genlmsghdr * genlhdr;
79 void * userhdr;
80 struct nlattr ** attrs;
Johannes Berg134e6372009-07-10 09:51:34 +000081#ifdef CONFIG_NET_NS
82 struct net * _net;
83#endif
Johannes Bergff4c92d2010-10-04 21:14:03 +020084 void * user_ptr[2];
Thomas Graf482a8522005-11-10 02:25:56 +010085};
86
Johannes Berg134e6372009-07-10 09:51:34 +000087static inline struct net *genl_info_net(struct genl_info *info)
88{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000089 return read_pnet(&info->_net);
Johannes Berg134e6372009-07-10 09:51:34 +000090}
91
92static inline void genl_info_net_set(struct genl_info *info, struct net *net)
93{
Eric Dumazetc2d9ba92010-06-01 06:51:19 +000094 write_pnet(&info->_net, net);
Johannes Berg134e6372009-07-10 09:51:34 +000095}
Johannes Berg134e6372009-07-10 09:51:34 +000096
Thomas Graf482a8522005-11-10 02:25:56 +010097/**
98 * struct genl_ops - generic netlink operations
99 * @cmd: command identifier
Johannes Bergff4c92d2010-10-04 21:14:03 +0200100 * @internal_flags: flags used by the family
Thomas Graf482a8522005-11-10 02:25:56 +0100101 * @flags: flags
102 * @policy: attribute validation policy
103 * @doit: standard command callback
104 * @dumpit: callback for dumpers
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800105 * @done: completion callback for dumps
Thomas Graf482a8522005-11-10 02:25:56 +0100106 * @ops_list: operations list
107 */
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +0000108struct genl_ops {
Per Lidenb461d2f2006-01-03 14:13:29 -0800109 u8 cmd;
Johannes Bergff4c92d2010-10-04 21:14:03 +0200110 u8 internal_flags;
Thomas Graf482a8522005-11-10 02:25:56 +0100111 unsigned int flags;
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700112 const struct nla_policy *policy;
Thomas Graf482a8522005-11-10 02:25:56 +0100113 int (*doit)(struct sk_buff *skb,
114 struct genl_info *info);
115 int (*dumpit)(struct sk_buff *skb,
116 struct netlink_callback *cb);
Jamal Hadi Salima4d13662006-12-01 20:07:42 -0800117 int (*done)(struct netlink_callback *cb);
Thomas Graf482a8522005-11-10 02:25:56 +0100118 struct list_head ops_list;
119};
120
121extern int genl_register_family(struct genl_family *family);
Michał Mirosława7b11d72009-05-21 10:34:04 +0000122extern int genl_register_family_with_ops(struct genl_family *family,
123 struct genl_ops *ops, size_t n_ops);
Thomas Graf482a8522005-11-10 02:25:56 +0100124extern 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);
Johannes Berg2dbba6f2007-07-18 15:47:52 -0700127extern 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);
Thomas Graf482a8522005-11-10 02:25:56 +0100131
Thomas Graf482a8522005-11-10 02:25:56 +0100132/**
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)
Thomas Graf17c157c2006-11-14 19:46:02 -0800137 * @family: generic netlink family
Thomas Graf482a8522005-11-10 02:25:56 +0100138 * @flags netlink message flags
139 * @cmd: generic netlink command
Thomas Graf482a8522005-11-10 02:25:56 +0100140 *
141 * Returns pointer to user specific header
142 */
143static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
Thomas Graf17c157c2006-11-14 19:46:02 -0800144 struct genl_family *family, int flags, u8 cmd)
Thomas Graf482a8522005-11-10 02:25:56 +0100145{
146 struct nlmsghdr *nlh;
147 struct genlmsghdr *hdr;
148
Thomas Graf17c157c2006-11-14 19:46:02 -0800149 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
150 family->hdrsize, flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100151 if (nlh == NULL)
152 return NULL;
153
154 hdr = nlmsg_data(nlh);
155 hdr->cmd = cmd;
Thomas Graf17c157c2006-11-14 19:46:02 -0800156 hdr->version = family->version;
Thomas Graf482a8522005-11-10 02:25:56 +0100157 hdr->reserved = 0;
158
159 return (char *) hdr + GENL_HDRLEN;
160}
161
162/**
Thomas Graf17c157c2006-11-14 19:46:02 -0800163 * genlmsg_put_reply - Add generic netlink header to a reply message
164 * @skb: socket buffer holding the message
165 * @info: receiver info
166 * @family: generic netlink family
167 * @flags: netlink message flags
168 * @cmd: generic netlink command
169 *
170 * Returns pointer to user specific header
171 */
172static inline void *genlmsg_put_reply(struct sk_buff *skb,
173 struct genl_info *info,
174 struct genl_family *family,
175 int flags, u8 cmd)
176{
177 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family,
178 flags, cmd);
179}
180
181/**
Thomas Graf482a8522005-11-10 02:25:56 +0100182 * genlmsg_end - Finalize a generic netlink message
183 * @skb: socket buffer the message is stored in
184 * @hdr: user specific header
185 */
186static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
187{
188 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
189}
190
191/**
192 * genlmsg_cancel - Cancel construction of a generic netlink message
193 * @skb: socket buffer the message is stored in
194 * @hdr: generic netlink message header
195 */
Thomas Grafbc3ed282008-06-03 16:36:54 -0700196static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
Thomas Graf482a8522005-11-10 02:25:56 +0100197{
Julia Lawall38db9e12011-01-28 05:43:40 +0000198 if (hdr)
199 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
Thomas Graf482a8522005-11-10 02:25:56 +0100200}
201
202/**
Johannes Berg134e6372009-07-10 09:51:34 +0000203 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
204 * @net: the net namespace
205 * @skb: netlink message as socket buffer
206 * @pid: own netlink pid to avoid sending to yourself
207 * @group: multicast group id
208 * @flags: allocation flags
209 */
210static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
211 u32 pid, unsigned int group, gfp_t flags)
212{
213 return nlmsg_multicast(net->genl_sock, skb, pid, group, flags);
214}
215
216/**
217 * genlmsg_multicast - multicast a netlink message to the default netns
Thomas Graf482a8522005-11-10 02:25:56 +0100218 * @skb: netlink message as socket buffer
219 * @pid: own netlink pid to avoid sending to yourself
220 * @group: multicast group id
Thomas Grafd387f6a2006-08-15 00:31:06 -0700221 * @flags: allocation flags
Thomas Graf482a8522005-11-10 02:25:56 +0100222 */
223static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
Thomas Grafd387f6a2006-08-15 00:31:06 -0700224 unsigned int group, gfp_t flags)
Thomas Graf482a8522005-11-10 02:25:56 +0100225{
Johannes Berg134e6372009-07-10 09:51:34 +0000226 return genlmsg_multicast_netns(&init_net, skb, pid, group, flags);
Thomas Graf482a8522005-11-10 02:25:56 +0100227}
228
229/**
Johannes Berg134e6372009-07-10 09:51:34 +0000230 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
231 * @skb: netlink message as socket buffer
232 * @pid: own netlink pid to avoid sending to yourself
233 * @group: multicast group id
234 * @flags: allocation flags
235 *
236 * This function must hold the RTNL or rcu_read_lock().
237 */
238int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid,
239 unsigned int group, gfp_t flags);
240
241/**
Thomas Graf482a8522005-11-10 02:25:56 +0100242 * genlmsg_unicast - unicast a netlink message
243 * @skb: netlink message as socket buffer
244 * @pid: netlink pid of the destination socket
245 */
Johannes Berg134e6372009-07-10 09:51:34 +0000246static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 pid)
Thomas Graf482a8522005-11-10 02:25:56 +0100247{
Johannes Berg134e6372009-07-10 09:51:34 +0000248 return nlmsg_unicast(net->genl_sock, skb, pid);
Thomas Graf482a8522005-11-10 02:25:56 +0100249}
250
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700251/**
Thomas Graf81878d22006-11-14 19:45:27 -0800252 * genlmsg_reply - reply to a request
253 * @skb: netlink message to be sent back
254 * @info: receiver information
255 */
256static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
257{
Johannes Berg134e6372009-07-10 09:51:34 +0000258 return genlmsg_unicast(genl_info_net(info), skb, info->snd_pid);
Thomas Graf81878d22006-11-14 19:45:27 -0800259}
260
261/**
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700262 * gennlmsg_data - head of message payload
Justin P. Mattock70f23fd2011-05-10 10:16:21 +0200263 * @gnlh: genetlink message header
Balbir Singhfb0ba6bd2006-07-14 00:24:39 -0700264 */
265static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
266{
267 return ((unsigned char *) gnlh + GENL_HDRLEN);
268}
269
270/**
271 * genlmsg_len - length of message payload
272 * @gnlh: genetlink message header
273 */
274static inline int genlmsg_len(const struct genlmsghdr *gnlh)
275{
276 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
277 NLMSG_HDRLEN);
278 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
279}
280
Balbir Singh17db9522006-09-30 23:28:51 -0700281/**
282 * genlmsg_msg_size - length of genetlink message not including padding
283 * @payload: length of message payload
284 */
285static inline int genlmsg_msg_size(int payload)
286{
287 return GENL_HDRLEN + payload;
288}
289
290/**
291 * genlmsg_total_size - length of genetlink message including padding
292 * @payload: length of message payload
293 */
294static inline int genlmsg_total_size(int payload)
295{
296 return NLMSG_ALIGN(genlmsg_msg_size(payload));
297}
298
Thomas Graf3dabc712006-11-14 19:44:52 -0800299/**
300 * genlmsg_new - Allocate a new generic netlink message
301 * @payload: size of the message payload
302 * @flags: the type of memory to allocate.
303 */
304static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
305{
306 return nlmsg_new(genlmsg_total_size(payload), flags);
307}
308
309
Thomas Graf482a8522005-11-10 02:25:56 +0100310#endif /* __NET_GENERIC_NETLINK_H */