include/net/genetlink.h

   1 #ifndef __NET_GENERIC_NETLINK_H
   2 #define __NET_GENERIC_NETLINK_H
   3
   4 #include <linux/genetlink.h>
   5 #include <net/netlink.h>
   6
   7 /**
   8  * struct genl_family - generic netlink family
   9  * @id: protocol family idenfitier
  10  * @hdrsize: length of user specific header in bytes
  11  * @name: name of family
  12  * @version: protocol version
  13  * @maxattr: maximum number of attributes supported
  14  * @attrbuf: buffer to store parsed attributes
  15  * @ops_list: list of all assigned operations
  16  * @family_list: family list
  17  */
  18 struct genl_family
  19 {
  20         unsigned int            id;
  21         unsigned int            hdrsize;
  22         char                    name[GENL_NAMSIZ];
  23         unsigned int            version;
  24         unsigned int            maxattr;
  25         struct module *         owner;
  26         struct nlattr **        attrbuf;        /* private */
  27         struct list_head        ops_list;       /* private */
  28         struct list_head        family_list;    /* private */
  29 };
  30
  31 #define GENL_ADMIN_PERM         0x01
  32
  33 /**
  34  * struct genl_info - receiving information
  35  * @snd_seq: sending sequence number
  36  * @snd_pid: netlink pid of sender
  37  * @nlhdr: netlink message header
  38  * @genlhdr: generic netlink message header
  39  * @userhdr: user specific header
  40  * @attrs: netlink attributes
  41  */
  42 struct genl_info
  43 {
  44         u32                     snd_seq;
  45         u32                     snd_pid;
  46         struct nlmsghdr *       nlhdr;
  47         struct genlmsghdr *     genlhdr;
  48         void *                  userhdr;
  49         struct nlattr **        attrs;
  50 };
  51
  52 /**
  53  * struct genl_ops - generic netlink operations
  54  * @cmd: command identifier
  55  * @flags: flags
  56  * @policy: attribute validation policy
  57  * @doit: standard command callback
  58  * @dumpit: callback for dumpers
  59  * @ops_list: operations list
  60  */
  61 struct genl_ops
  62 {
  63         u8                      cmd;
  64         unsigned int            flags;
  65         struct nla_policy       *policy;
  66         int                    (*doit)(struct sk_buff *skb,
  67                                        struct genl_info *info);
  68         int                    (*dumpit)(struct sk_buff *skb,
  69                                          struct netlink_callback *cb);
  70         struct list_head        ops_list;
  71 };
  72
  73 extern int genl_register_family(struct genl_family *family);
  74 extern int genl_unregister_family(struct genl_family *family);
  75 extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
  76 extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
  77
  78 extern struct sock *genl_sock;
  79
  80 /**
  81  * genlmsg_put - Add generic netlink header to netlink message
  82  * @skb: socket buffer holding the message
  83  * @pid: netlink pid the message is addressed to
  84  * @seq: sequence number (usually the one of the sender)
  85  * @type: netlink message type
  86  * @hdrlen: length of the user specific header
  87  * @flags netlink message flags
  88  * @cmd: generic netlink command
  89  * @version: version
  90  *
  91  * Returns pointer to user specific header
  92  */
  93 static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
  94                                 int type, int hdrlen, int flags,
  95                                 u8 cmd, u8 version)
  96 {
  97         struct nlmsghdr *nlh;
  98         struct genlmsghdr *hdr;
  99
 100         nlh = nlmsg_put(skb, pid, seq, type, GENL_HDRLEN + hdrlen, flags);
 101         if (nlh == NULL)
 102                 return NULL;
 103
 104         hdr = nlmsg_data(nlh);
 105         hdr->cmd = cmd;
 106         hdr->version = version;
 107         hdr->reserved = 0;
 108
 109         return (char *) hdr + GENL_HDRLEN;
 110 }
 111
 112 /**
 113  * genlmsg_end - Finalize a generic netlink message
 114  * @skb: socket buffer the message is stored in
 115  * @hdr: user specific header
 116  */
 117 static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
 118 {
 119         return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
 120 }
 121
 122 /**
 123  * genlmsg_cancel - Cancel construction of a generic netlink message
 124  * @skb: socket buffer the message is stored in
 125  * @hdr: generic netlink message header
 126  */
 127 static inline int genlmsg_cancel(struct sk_buff *skb, void *hdr)
 128 {
 129         return nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
 130 }
 131
 132 /**
 133  * genlmsg_multicast - multicast a netlink message
 134  * @skb: netlink message as socket buffer
 135  * @pid: own netlink pid to avoid sending to yourself
 136  * @group: multicast group id
 137  */
 138 static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
 139                                     unsigned int group)
 140 {
 141         return nlmsg_multicast(genl_sock, skb, pid, group);
 142 }
 143
 144 /**
 145  * genlmsg_unicast - unicast a netlink message
 146  * @skb: netlink message as socket buffer
 147  * @pid: netlink pid of the destination socket
 148  */
 149 static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid)
 150 {
 151         return nlmsg_unicast(genl_sock, skb, pid);
 152 }
 153
 154 #endif  /* __NET_GENERIC_NETLINK_H */