#ifndef __NET_GENERIC_NETLINK_H #define __NET_GENERIC_NETLINK_H #include <linux/genetlink.h> #include <net/netlink.h> #include <net/net_namespace.h> /** * struct genl_multicast_group - generic netlink multicast group * @name: name of the multicast group, names are per-family * @id: multicast group ID, assigned by the core, to use with * genlmsg_multicast(). * @list: list entry for linking * @family: pointer to family, need not be set before registering */ struct genl_multicast_group { struct genl_family *family; /* private */ struct list_head list; /* private */ char name[GENL_NAMSIZ]; u32 id; }; /** * struct genl_family - generic netlink family * @id: protocol family idenfitier * @hdrsize: length of user specific header in bytes * @name: name of family * @version: protocol version * @maxattr: maximum number of attributes supported * @netnsok: set to true if the family can handle network * namespaces and should be presented in all of them * @attrbuf: buffer to store parsed attributes * @ops_list: list of all assigned operations * @family_list: family list * @mcast_groups: multicast groups list */ struct genl_family { unsigned int id; unsigned int hdrsize; char name[GENL_NAMSIZ]; unsigned int version; unsigned int maxattr; bool netnsok; struct nlattr ** attrbuf; /* private */ struct list_head ops_list; /* private */ struct list_head family_list; /* private */ struct list_head mcast_groups; /* private */ }; /** * struct genl_info - receiving information * @snd_seq: sending sequence number * @snd_pid: netlink pid of sender * @nlhdr: netlink message header * @genlhdr: generic netlink message header * @userhdr: user specific header * @attrs: netlink attributes */ struct genl_info { u32 snd_seq; u32 snd_pid; struct nlmsghdr * nlhdr; struct genlmsghdr * genlhdr; void * userhdr; struct nlattr ** attrs; #ifdef CONFIG_NET_NS struct net * _net; #endif }; #ifdef CONFIG_NET_NS static inline struct net *genl_info_net(struct genl_info *info) { return info->_net; } static inline void genl_info_net_set(struct genl_info *info, struct net *net) { info->_net = net; } #else static inline struct net *genl_info_net(struct genl_info *info) { return &init_net; } static inline void genl_info_net_set(struct genl_info *info, struct net *net) { } #endif /** * struct genl_ops - generic netlink operations * @cmd: command identifier * @flags: flags * @policy: attribute validation policy * @doit: standard command callback * @dumpit: callback for dumpers * @done: completion callback for dumps * @ops_list: operations list */ struct genl_ops { u8 cmd; unsigned int flags; const struct nla_policy *policy; int (*doit)(struct sk_buff *skb, struct genl_info *info); int (*dumpit)(struct sk_buff *skb, struct netlink_callback *cb); int (*done)(struct netlink_callback *cb); struct list_head ops_list; }; extern int genl_register_family(struct genl_family *family); extern int genl_register_family_with_ops(struct genl_family *family, struct genl_ops *ops, size_t n_ops); extern int genl_unregister_family(struct genl_family *family); extern int genl_register_ops(struct genl_family *, struct genl_ops *ops); extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops); extern int genl_register_mc_group(struct genl_family *family, struct genl_multicast_group *grp); extern void genl_unregister_mc_group(struct genl_family *family, struct genl_multicast_group *grp); /** * genlmsg_put - Add generic netlink header to netlink message * @skb: socket buffer holding the message * @pid: netlink pid the message is addressed to * @seq: sequence number (usually the one of the sender) * @family: generic netlink family * @flags netlink message flags * @cmd: generic netlink command * * Returns pointer to user specific header */ static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, struct genl_family *family, int flags, u8 cmd) { struct nlmsghdr *nlh; struct genlmsghdr *hdr; nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN + family->hdrsize, flags); if (nlh == NULL) return NULL; hdr = nlmsg_data(nlh); hdr->cmd = cmd; hdr->version = family->version; hdr->reserved = 0; return (char *) hdr + GENL_HDRLEN; } /** * genlmsg_put_reply - Add generic netlink header to a reply message * @skb: socket buffer holding the message * @info: receiver info * @family: generic netlink family * @flags: netlink message flags * @cmd: generic netlink command * * Returns pointer to user specific header */ static inline void *genlmsg_put_reply(struct sk_buff *skb, struct genl_info *info, struct genl_family *family, int flags, u8 cmd) { return genlmsg_put(skb, info->snd_pid, info->snd_seq, family, flags, cmd); } /** * genlmsg_end - Finalize a generic netlink message * @skb: socket buffer the message is stored in * @hdr: user specific header */ static inline int genlmsg_end(struct sk_buff *skb, void *hdr) { return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); } /** * genlmsg_cancel - Cancel construction of a generic netlink message * @skb: socket buffer the message is stored in * @hdr: generic netlink message header */ static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr) { nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN); } /** * genlmsg_multicast_netns - multicast a netlink message to a specific netns * @net: the net namespace * @skb: netlink message as socket buffer * @pid: own netlink pid to avoid sending to yourself * @group: multicast group id * @flags: allocation flags */ static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb, u32 pid, unsigned int group, gfp_t flags) { return nlmsg_multicast(net->genl_sock, skb, pid, group, flags); } /** * genlmsg_multicast - multicast a netlink message to the default netns * @skb: netlink message as socket buffer * @pid: own netlink pid to avoid sending to yourself * @group: multicast group id * @flags: allocation flags */ static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid, unsigned int group, gfp_t flags) { return genlmsg_multicast_netns(&init_net, skb, pid, group, flags); } /** * genlmsg_multicast_allns - multicast a netlink message to all net namespaces * @skb: netlink message as socket buffer * @pid: own netlink pid to avoid sending to yourself * @group: multicast group id * @flags: allocation flags * * This function must hold the RTNL or rcu_read_lock(). */ int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group, gfp_t flags); /** * genlmsg_unicast - unicast a netlink message * @skb: netlink message as socket buffer * @pid: netlink pid of the destination socket */ static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 pid) { return nlmsg_unicast(net->genl_sock, skb, pid); } /** * genlmsg_reply - reply to a request * @skb: netlink message to be sent back * @info: receiver information */ static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info) { return genlmsg_unicast(genl_info_net(info), skb, info->snd_pid); } /** * gennlmsg_data - head of message payload * @gnlh: genetlink messsage header */ static inline void *genlmsg_data(const struct genlmsghdr *gnlh) { return ((unsigned char *) gnlh + GENL_HDRLEN); } /** * genlmsg_len - length of message payload * @gnlh: genetlink message header */ static inline int genlmsg_len(const struct genlmsghdr *gnlh) { struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh - NLMSG_HDRLEN); return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN); } /** * genlmsg_msg_size - length of genetlink message not including padding * @payload: length of message payload */ static inline int genlmsg_msg_size(int payload) { return GENL_HDRLEN + payload; } /** * genlmsg_total_size - length of genetlink message including padding * @payload: length of message payload */ static inline int genlmsg_total_size(int payload) { return NLMSG_ALIGN(genlmsg_msg_size(payload)); } /** * genlmsg_new - Allocate a new generic netlink message * @payload: size of the message payload * @flags: the type of memory to allocate. */ static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags) { return nlmsg_new(genlmsg_total_size(payload), flags); } #endif /* __NET_GENERIC_NETLINK_H */