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