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_register_family_with_ops(struct genl_family *family, 92 struct genl_ops *ops, size_t n_ops); 93 extern int genl_unregister_family(struct genl_family *family); 94 extern int genl_register_ops(struct genl_family *, struct genl_ops *ops); 95 extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops); 96 extern int genl_register_mc_group(struct genl_family *family, 97 struct genl_multicast_group *grp); 98 extern void genl_unregister_mc_group(struct genl_family *family, 99 struct genl_multicast_group *grp); 100 101 extern struct sock *genl_sock; 102 103 /** 104 * genlmsg_put - Add generic netlink header to netlink message 105 * @skb: socket buffer holding the message 106 * @pid: netlink pid the message is addressed to 107 * @seq: sequence number (usually the one of the sender) 108 * @family: generic netlink family 109 * @flags netlink message flags 110 * @cmd: generic netlink command 111 * 112 * Returns pointer to user specific header 113 */ 114 static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, 115 struct genl_family *family, int flags, u8 cmd) 116 { 117 struct nlmsghdr *nlh; 118 struct genlmsghdr *hdr; 119 120 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN + 121 family->hdrsize, flags); 122 if (nlh == NULL) 123 return NULL; 124 125 hdr = nlmsg_data(nlh); 126 hdr->cmd = cmd; 127 hdr->version = family->version; 128 hdr->reserved = 0; 129 130 return (char *) hdr + GENL_HDRLEN; 131 } 132 133 /** 134 * genlmsg_put_reply - Add generic netlink header to a reply message 135 * @skb: socket buffer holding the message 136 * @info: receiver info 137 * @family: generic netlink family 138 * @flags: netlink message flags 139 * @cmd: generic netlink command 140 * 141 * Returns pointer to user specific header 142 */ 143 static inline void *genlmsg_put_reply(struct sk_buff *skb, 144 struct genl_info *info, 145 struct genl_family *family, 146 int flags, u8 cmd) 147 { 148 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family, 149 flags, cmd); 150 } 151 152 /** 153 * genlmsg_end - Finalize a generic netlink message 154 * @skb: socket buffer the message is stored in 155 * @hdr: user specific header 156 */ 157 static inline int genlmsg_end(struct sk_buff *skb, void *hdr) 158 { 159 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); 160 } 161 162 /** 163 * genlmsg_cancel - Cancel construction of a generic netlink message 164 * @skb: socket buffer the message is stored in 165 * @hdr: generic netlink message header 166 */ 167 static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr) 168 { 169 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); 170 } 171 172 /** 173 * genlmsg_multicast - multicast a netlink message 174 * @skb: netlink message as socket buffer 175 * @pid: own netlink pid to avoid sending to yourself 176 * @group: multicast group id 177 * @flags: allocation flags 178 */ 179 static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid, 180 unsigned int group, gfp_t flags) 181 { 182 return nlmsg_multicast(genl_sock, skb, pid, group, flags); 183 } 184 185 /** 186 * genlmsg_unicast - unicast a netlink message 187 * @skb: netlink message as socket buffer 188 * @pid: netlink pid of the destination socket 189 */ 190 static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid) 191 { 192 return nlmsg_unicast(genl_sock, skb, pid); 193 } 194 195 /** 196 * genlmsg_reply - reply to a request 197 * @skb: netlink message to be sent back 198 * @info: receiver information 199 */ 200 static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info) 201 { 202 return genlmsg_unicast(skb, info->snd_pid); 203 } 204 205 /** 206 * gennlmsg_data - head of message payload 207 * @gnlh: genetlink messsage header 208 */ 209 static inline void *genlmsg_data(const struct genlmsghdr *gnlh) 210 { 211 return ((unsigned char *) gnlh + GENL_HDRLEN); 212 } 213 214 /** 215 * genlmsg_len - length of message payload 216 * @gnlh: genetlink message header 217 */ 218 static inline int genlmsg_len(const struct genlmsghdr *gnlh) 219 { 220 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh - 221 NLMSG_HDRLEN); 222 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN); 223 } 224 225 /** 226 * genlmsg_msg_size - length of genetlink message not including padding 227 * @payload: length of message payload 228 */ 229 static inline int genlmsg_msg_size(int payload) 230 { 231 return GENL_HDRLEN + payload; 232 } 233 234 /** 235 * genlmsg_total_size - length of genetlink message including padding 236 * @payload: length of message payload 237 */ 238 static inline int genlmsg_total_size(int payload) 239 { 240 return NLMSG_ALIGN(genlmsg_msg_size(payload)); 241 } 242 243 /** 244 * genlmsg_new - Allocate a new generic netlink message 245 * @payload: size of the message payload 246 * @flags: the type of memory to allocate. 247 */ 248 static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags) 249 { 250 return nlmsg_new(genlmsg_total_size(payload), flags); 251 } 252 253 254 #endif /* __NET_GENERIC_NETLINK_H */ 255