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_multicast_group - generic netlink multicast group 9 * @name: name of the multicast group, names are per-family 10 * @id: multicast group ID, assigned by the core, to use with 11 * genlmsg_multicast(). 12 * @list: list entry for linking 13 * @family: pointer to family, need not be set before registering 14 */ 15 struct genl_multicast_group 16 { 17 struct genl_family *family; /* private */ 18 struct list_head list; /* private */ 19 char name[GENL_NAMSIZ]; 20 u32 id; 21 }; 22 23 /** 24 * struct genl_family - generic netlink family 25 * @id: protocol family idenfitier 26 * @hdrsize: length of user specific header in bytes 27 * @name: name of family 28 * @version: protocol version 29 * @maxattr: maximum number of attributes supported 30 * @attrbuf: buffer to store parsed attributes 31 * @ops_list: list of all assigned operations 32 * @family_list: family list 33 * @mcast_groups: multicast groups list 34 */ 35 struct genl_family 36 { 37 unsigned int id; 38 unsigned int hdrsize; 39 char name[GENL_NAMSIZ]; 40 unsigned int version; 41 unsigned int maxattr; 42 struct nlattr ** attrbuf; /* private */ 43 struct list_head ops_list; /* private */ 44 struct list_head family_list; /* private */ 45 struct list_head mcast_groups; /* private */ 46 }; 47 48 /** 49 * struct genl_info - receiving information 50 * @snd_seq: sending sequence number 51 * @snd_pid: netlink pid of sender 52 * @nlhdr: netlink message header 53 * @genlhdr: generic netlink message header 54 * @userhdr: user specific header 55 * @attrs: netlink attributes 56 */ 57 struct genl_info 58 { 59 u32 snd_seq; 60 u32 snd_pid; 61 struct nlmsghdr * nlhdr; 62 struct genlmsghdr * genlhdr; 63 void * userhdr; 64 struct nlattr ** attrs; 65 }; 66 67 /** 68 * struct genl_ops - generic netlink operations 69 * @cmd: command identifier 70 * @flags: flags 71 * @policy: attribute validation policy 72 * @doit: standard command callback 73 * @dumpit: callback for dumpers 74 * @done: completion callback for dumps 75 * @ops_list: operations list 76 */ 77 struct genl_ops 78 { 79 u8 cmd; 80 unsigned int flags; 81 const struct nla_policy *policy; 82 int (*doit)(struct sk_buff *skb, 83 struct genl_info *info); 84 int (*dumpit)(struct sk_buff *skb, 85 struct netlink_callback *cb); 86 int (*done)(struct netlink_callback *cb); 87 struct list_head ops_list; 88 }; 89 90 extern int genl_register_family(struct genl_family *family); 91 extern int genl_unregister_family(struct genl_family *family); 92 extern int genl_register_ops(struct genl_family *, struct genl_ops *ops); 93 extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops); 94 extern int genl_register_mc_group(struct genl_family *family, 95 struct genl_multicast_group *grp); 96 extern void genl_unregister_mc_group(struct genl_family *family, 97 struct genl_multicast_group *grp); 98 99 extern struct sock *genl_sock; 100 101 /** 102 * genlmsg_put - Add generic netlink header to netlink message 103 * @skb: socket buffer holding the message 104 * @pid: netlink pid the message is addressed to 105 * @seq: sequence number (usually the one of the sender) 106 * @family: generic netlink family 107 * @flags netlink message flags 108 * @cmd: generic netlink command 109 * 110 * Returns pointer to user specific header 111 */ 112 static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, 113 struct genl_family *family, int flags, u8 cmd) 114 { 115 struct nlmsghdr *nlh; 116 struct genlmsghdr *hdr; 117 118 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN + 119 family->hdrsize, flags); 120 if (nlh == NULL) 121 return NULL; 122 123 hdr = nlmsg_data(nlh); 124 hdr->cmd = cmd; 125 hdr->version = family->version; 126 hdr->reserved = 0; 127 128 return (char *) hdr + GENL_HDRLEN; 129 } 130 131 /** 132 * genlmsg_put_reply - Add generic netlink header to a reply message 133 * @skb: socket buffer holding the message 134 * @info: receiver info 135 * @family: generic netlink family 136 * @flags: netlink message flags 137 * @cmd: generic netlink command 138 * 139 * Returns pointer to user specific header 140 */ 141 static inline void *genlmsg_put_reply(struct sk_buff *skb, 142 struct genl_info *info, 143 struct genl_family *family, 144 int flags, u8 cmd) 145 { 146 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family, 147 flags, cmd); 148 } 149 150 /** 151 * genlmsg_end - Finalize a generic netlink message 152 * @skb: socket buffer the message is stored in 153 * @hdr: user specific header 154 */ 155 static inline int genlmsg_end(struct sk_buff *skb, void *hdr) 156 { 157 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); 158 } 159 160 /** 161 * genlmsg_cancel - Cancel construction of a generic netlink message 162 * @skb: socket buffer the message is stored in 163 * @hdr: generic netlink message header 164 */ 165 static inline int genlmsg_cancel(struct sk_buff *skb, void *hdr) 166 { 167 return nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); 168 } 169 170 /** 171 * genlmsg_multicast - multicast a netlink message 172 * @skb: netlink message as socket buffer 173 * @pid: own netlink pid to avoid sending to yourself 174 * @group: multicast group id 175 * @flags: allocation flags 176 */ 177 static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid, 178 unsigned int group, gfp_t flags) 179 { 180 return nlmsg_multicast(genl_sock, skb, pid, group, flags); 181 } 182 183 /** 184 * genlmsg_unicast - unicast a netlink message 185 * @skb: netlink message as socket buffer 186 * @pid: netlink pid of the destination socket 187 */ 188 static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid) 189 { 190 return nlmsg_unicast(genl_sock, skb, pid); 191 } 192 193 /** 194 * genlmsg_reply - reply to a request 195 * @skb: netlink message to be sent back 196 * @info: receiver information 197 */ 198 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info) 199 { 200 return genlmsg_unicast(skb, info->snd_pid); 201 } 202 203 /** 204 * gennlmsg_data - head of message payload 205 * @gnlh: genetlink messsage header 206 */ 207 static inline void *genlmsg_data(const struct genlmsghdr *gnlh) 208 { 209 return ((unsigned char *) gnlh + GENL_HDRLEN); 210 } 211 212 /** 213 * genlmsg_len - length of message payload 214 * @gnlh: genetlink message header 215 */ 216 static inline int genlmsg_len(const struct genlmsghdr *gnlh) 217 { 218 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh - 219 NLMSG_HDRLEN); 220 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN); 221 } 222 223 /** 224 * genlmsg_msg_size - length of genetlink message not including padding 225 * @payload: length of message payload 226 */ 227 static inline int genlmsg_msg_size(int payload) 228 { 229 return GENL_HDRLEN + payload; 230 } 231 232 /** 233 * genlmsg_total_size - length of genetlink message including padding 234 * @payload: length of message payload 235 */ 236 static inline int genlmsg_total_size(int payload) 237 { 238 return NLMSG_ALIGN(genlmsg_msg_size(payload)); 239 } 240 241 /** 242 * genlmsg_new - Allocate a new generic netlink message 243 * @payload: size of the message payload 244 * @flags: the type of memory to allocate. 245 */ 246 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags) 247 { 248 return nlmsg_new(genlmsg_total_size(payload), flags); 249 } 250 251 252 #endif /* __NET_GENERIC_NETLINK_H */ 253