initial_commit

1 files changed, 310 insertions, 0 deletions

diff --git a/include/net/genetlink.h b/include/net/genetlink.h
new file mode 100644
index 00000000..d420f28b
--- /dev/null
+++ b/include/net/genetlink.h
@@ -0,0 +1,310 @@
+#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_ops;
+struct genl_info;
+
+/**
+ * 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
+ * @pre_doit: called before an operation's doit callback, it may
+ *	do additional, common, filtering and return an error
+ * @post_doit: called after an operation's doit callback, it may
+ *	undo operations done by pre_doit, for example release locks
+ * @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;
+	int			(*pre_doit)(struct genl_ops *ops,
+					    struct sk_buff *skb,
+					    struct genl_info *info);
+	void			(*post_doit)(struct genl_ops *ops,
+					     struct sk_buff *skb,
+					     struct genl_info *info);
+	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
+ * @_net: network namespace
+ * @user_ptr: user pointers
+ */
+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
+	void *			user_ptr[2];
+};
+
+static inline struct net *genl_info_net(struct genl_info *info)
+{
+	return read_pnet(&info->_net);
+}
+
+static inline void genl_info_net_set(struct genl_info *info, struct net *net)
+{
+	write_pnet(&info->_net, net);
+}
+
+/**
+ * struct genl_ops - generic netlink operations
+ * @cmd: command identifier
+ * @internal_flags: flags used by the family
+ * @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;
+	u8			internal_flags;
+	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)
+{
+	if (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 message 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 */