[linux-2.6-block.git] / include / linux / netlink.h

#ifndef __LINUX_NETLINK_H
#define __LINUX_NETLINK_H

#include <linux/socket.h> /* for __kernel_sa_family_t */
#include <linux/types.h>

#define NETLINK_ROUTE		0	/* Routing/device hook				*/
#define NETLINK_UNUSED		1	/* Unused number				*/
#define NETLINK_USERSOCK	2	/* Reserved for user mode socket protocols 	*/
#define NETLINK_FIREWALL	3	/* Unused number, formerly ip_queue		*/
#define NETLINK_SOCK_DIAG	4	/* socket monitoring				*/
#define NETLINK_NFLOG		5	/* netfilter/iptables ULOG */
#define NETLINK_XFRM		6	/* ipsec */
#define NETLINK_SELINUX		7	/* SELinux event notifications */
#define NETLINK_ISCSI		8	/* Open-iSCSI */
#define NETLINK_AUDIT		9	/* auditing */
#define NETLINK_FIB_LOOKUP	10	
#define NETLINK_CONNECTOR	11
#define NETLINK_NETFILTER	12	/* netfilter subsystem */
#define NETLINK_IP6_FW		13
#define NETLINK_DNRTMSG		14	/* DECnet routing messages */
#define NETLINK_KOBJECT_UEVENT	15	/* Kernel messages to userspace */
#define NETLINK_GENERIC		16
/* leave room for NETLINK_DM (DM Events) */
#define NETLINK_SCSITRANSPORT	18	/* SCSI Transports */
#define NETLINK_ECRYPTFS	19
#define NETLINK_RDMA		20
#define NETLINK_CRYPTO		21	/* Crypto layer */

#define NETLINK_INET_DIAG	NETLINK_SOCK_DIAG

#define MAX_LINKS 32		

struct sockaddr_nl {
	__kernel_sa_family_t	nl_family;	/* AF_NETLINK	*/
	unsigned short	nl_pad;		/* zero		*/
	__u32		nl_pid;		/* port ID	*/
       	__u32		nl_groups;	/* multicast groups mask */
};

struct nlmsghdr {
	__u32		nlmsg_len;	/* Length of message including header */
	__u16		nlmsg_type;	/* Message content */
	__u16		nlmsg_flags;	/* Additional flags */
	__u32		nlmsg_seq;	/* Sequence number */
	__u32		nlmsg_pid;	/* Sending process port ID */
};

/* Flags values */

#define NLM_F_REQUEST		1	/* It is request message. 	*/
#define NLM_F_MULTI		2	/* Multipart message, terminated by NLMSG_DONE */
#define NLM_F_ACK		4	/* Reply with ack, with zero or error code */
#define NLM_F_ECHO		8	/* Echo this request 		*/
#define NLM_F_DUMP_INTR		16	/* Dump was inconsistent due to sequence change */

/* Modifiers to GET request */
#define NLM_F_ROOT	0x100	/* specify tree	root	*/
#define NLM_F_MATCH	0x200	/* return all matching	*/
#define NLM_F_ATOMIC	0x400	/* atomic GET		*/
#define NLM_F_DUMP	(NLM_F_ROOT|NLM_F_MATCH)

/* Modifiers to NEW request */
#define NLM_F_REPLACE	0x100	/* Override existing		*/
#define NLM_F_EXCL	0x200	/* Do not touch, if it exists	*/
#define NLM_F_CREATE	0x400	/* Create, if it does not exist	*/
#define NLM_F_APPEND	0x800	/* Add to end of list		*/

/*
   4.4BSD ADD		NLM_F_CREATE|NLM_F_EXCL
   4.4BSD CHANGE	NLM_F_REPLACE

   True CHANGE		NLM_F_CREATE|NLM_F_REPLACE
   Append		NLM_F_CREATE
   Check		NLM_F_EXCL
 */

#define NLMSG_ALIGNTO	4U
#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
#define NLMSG_HDRLEN	 ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
#define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
#define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
#define NLMSG_NEXT(nlh,len)	 ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
				  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
			   (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
			   (nlh)->nlmsg_len <= (len))
#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))

#define NLMSG_NOOP		0x1	/* Nothing.		*/
#define NLMSG_ERROR		0x2	/* Error		*/
#define NLMSG_DONE		0x3	/* End of a dump	*/
#define NLMSG_OVERRUN		0x4	/* Data lost		*/

#define NLMSG_MIN_TYPE		0x10	/* < 0x10: reserved control messages */

struct nlmsgerr {
	int		error;
	struct nlmsghdr msg;
};

#define NETLINK_ADD_MEMBERSHIP	1
#define NETLINK_DROP_MEMBERSHIP	2
#define NETLINK_PKTINFO		3
#define NETLINK_BROADCAST_ERROR	4
#define NETLINK_NO_ENOBUFS	5

struct nl_pktinfo {
	__u32	group;
};

#define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/

enum {
	NETLINK_UNCONNECTED = 0,
	NETLINK_CONNECTED,
};

/*
 *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
 * +---------------------+- - -+- - - - - - - - - -+- - -+
 * |        Header       | Pad |     Payload       | Pad |
 * |   (struct nlattr)   | ing |                   | ing |
 * +---------------------+- - -+- - - - - - - - - -+- - -+
 *  <-------------- nlattr->nla_len -------------->
 */

struct nlattr {
	__u16           nla_len;
	__u16           nla_type;
};

/*
 * nla_type (16 bits)
 * +---+---+-------------------------------+
 * | N | O | Attribute Type                |
 * +---+---+-------------------------------+
 * N := Carries nested attributes
 * O := Payload stored in network byte order
 *
 * Note: The N and O flag are mutually exclusive.
 */
#define NLA_F_NESTED		(1 << 15)
#define NLA_F_NET_BYTEORDER	(1 << 14)
#define NLA_TYPE_MASK		~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)

#define NLA_ALIGNTO		4
#define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
#define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))

#ifdef __KERNEL__

#include <linux/capability.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <net/scm.h>

struct net;

static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
{
	return (struct nlmsghdr *)skb->data;
}

struct netlink_skb_parms {
	struct scm_creds	creds;		/* Skb credentials	*/
	__u32			portid;
	__u32			dst_group;
	struct sock		*ssk;
};

#define NETLINK_CB(skb)		(*(struct netlink_skb_parms*)&((skb)->cb))
#define NETLINK_CREDS(skb)	(&NETLINK_CB((skb)).creds)


extern void netlink_table_grab(void);
extern void netlink_table_ungrab(void);

#define NL_CFG_F_NONROOT_RECV	(1 << 0)
#define NL_CFG_F_NONROOT_SEND	(1 << 1)

/* optional Netlink kernel configuration parameters */
struct netlink_kernel_cfg {
	unsigned int	groups;
	void		(*input)(struct sk_buff *skb);
	struct mutex	*cb_mutex;
	void		(*bind)(int group);
	unsigned int	flags;
};

extern struct sock *__netlink_kernel_create(struct net *net, int unit,
					    struct module *module,
					    struct netlink_kernel_cfg *cfg);
static inline struct sock *
netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg)
{
	return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
}

extern void netlink_kernel_release(struct sock *sk);
extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
extern int netlink_has_listeners(struct sock *sk, unsigned int group);
extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid,
			     __u32 group, gfp_t allocation);
extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
	__u32 portid, __u32 group, gfp_t allocation,
	int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
	void *filter_data);
extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
extern int netlink_register_notifier(struct notifier_block *nb);
extern int netlink_unregister_notifier(struct notifier_block *nb);

/* finegrained unicast helpers: */
struct sock *netlink_getsockbyfilp(struct file *filp);
int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
		      long *timeo, struct sock *ssk);
void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
int netlink_sendskb(struct sock *sk, struct sk_buff *skb);

/*
 *	skb should fit one page. This choice is good for headerless malloc.
 *	But we should limit to 8K so that userspace does not have to
 *	use enormous buffer sizes on recvmsg() calls just to avoid
 *	MSG_TRUNC when PAGE_SIZE is very large.
 */
#if PAGE_SIZE < 8192UL
#define NLMSG_GOODSIZE	SKB_WITH_OVERHEAD(PAGE_SIZE)
#else
#define NLMSG_GOODSIZE	SKB_WITH_OVERHEAD(8192UL)
#endif

#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)


struct netlink_callback {
	struct sk_buff		*skb;
	const struct nlmsghdr	*nlh;
	int			(*dump)(struct sk_buff * skb,
					struct netlink_callback *cb);
	int			(*done)(struct netlink_callback *cb);
	void			*data;
	u16			family;
	u16			min_dump_alloc;
	unsigned int		prev_seq, seq;
	long			args[6];
};

struct netlink_notify {
	struct net *net;
	int portid;
	int protocol;
};

struct nlmsghdr *
__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);

struct netlink_dump_control {
	int (*dump)(struct sk_buff *skb, struct netlink_callback *);
	int (*done)(struct netlink_callback*);
	void *data;
	u16 min_dump_alloc;
};

extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
			      const struct nlmsghdr *nlh,
			      struct netlink_dump_control *control);

#endif /* __KERNEL__ */

#endif	/* __LINUX_NETLINK_H */
Commit	Line	Data
	1	#ifndef __LINUX_NETLINK_H
	2	#define __LINUX_NETLINK_H
	3
	4	#include <linux/socket.h> /* for __kernel_sa_family_t */
	5	#include <linux/types.h>
	6
	7	#define NETLINK_ROUTE 0 /* Routing/device hook */
	8	#define NETLINK_UNUSED 1 /* Unused number */
	9	#define NETLINK_USERSOCK 2 /* Reserved for user mode socket protocols */
	10	#define NETLINK_FIREWALL 3 /* Unused number, formerly ip_queue */
	11	#define NETLINK_SOCK_DIAG 4 /* socket monitoring */
	12	#define NETLINK_NFLOG 5 /* netfilter/iptables ULOG */
	13	#define NETLINK_XFRM 6 /* ipsec */
	14	#define NETLINK_SELINUX 7 /* SELinux event notifications */
	15	#define NETLINK_ISCSI 8 /* Open-iSCSI */
	16	#define NETLINK_AUDIT 9 /* auditing */
	17	#define NETLINK_FIB_LOOKUP 10
	18	#define NETLINK_CONNECTOR 11
	19	#define NETLINK_NETFILTER 12 /* netfilter subsystem */
	20	#define NETLINK_IP6_FW 13
	21	#define NETLINK_DNRTMSG 14 /* DECnet routing messages */
	22	#define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */
	23	#define NETLINK_GENERIC 16
	24	/* leave room for NETLINK_DM (DM Events) */
	25	#define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */
	26	#define NETLINK_ECRYPTFS 19
	27	#define NETLINK_RDMA 20
	28	#define NETLINK_CRYPTO 21 /* Crypto layer */
	29
	30	#define NETLINK_INET_DIAG NETLINK_SOCK_DIAG
	31
	32	#define MAX_LINKS 32
	33
	34	struct sockaddr_nl {
	35	__kernel_sa_family_t nl_family; /* AF_NETLINK */
	36	unsigned short nl_pad; /* zero */
	37	__u32 nl_pid; /* port ID */
	38	__u32 nl_groups; /* multicast groups mask */
	39	};
	40
	41	struct nlmsghdr {
	42	__u32 nlmsg_len; /* Length of message including header */
	43	__u16 nlmsg_type; /* Message content */
	44	__u16 nlmsg_flags; /* Additional flags */
	45	__u32 nlmsg_seq; /* Sequence number */
	46	__u32 nlmsg_pid; /* Sending process port ID */
	47	};
	48
	49	/* Flags values */
	50
	51	#define NLM_F_REQUEST 1 /* It is request message. */
	52	#define NLM_F_MULTI 2 /* Multipart message, terminated by NLMSG_DONE */
	53	#define NLM_F_ACK 4 /* Reply with ack, with zero or error code */
	54	#define NLM_F_ECHO 8 /* Echo this request */
	55	#define NLM_F_DUMP_INTR 16 /* Dump was inconsistent due to sequence change */
	56
	57	/* Modifiers to GET request */
	58	#define NLM_F_ROOT 0x100 /* specify tree root */
	59	#define NLM_F_MATCH 0x200 /* return all matching */
	60	#define NLM_F_ATOMIC 0x400 /* atomic GET */
	61	#define NLM_F_DUMP (NLM_F_ROOT\|NLM_F_MATCH)
	62
	63	/* Modifiers to NEW request */
	64	#define NLM_F_REPLACE 0x100 /* Override existing */
	65	#define NLM_F_EXCL 0x200 /* Do not touch, if it exists */
	66	#define NLM_F_CREATE 0x400 /* Create, if it does not exist */
	67	#define NLM_F_APPEND 0x800 /* Add to end of list */
	68
	69	/*
	70	4.4BSD ADD NLM_F_CREATE\|NLM_F_EXCL
	71	4.4BSD CHANGE NLM_F_REPLACE
	72
	73	True CHANGE NLM_F_CREATE\|NLM_F_REPLACE
	74	Append NLM_F_CREATE
	75	Check NLM_F_EXCL
	76	*/
	77
	78	#define NLMSG_ALIGNTO 4U
	79	#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
	80	#define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
	81	#define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
	82	#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
	83	#define NLMSG_DATA(nlh) ((void)(((char)nlh) + NLMSG_LENGTH(0)))
	84	#define NLMSG_NEXT(nlh,len) ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
	85	(struct nlmsghdr)(((char)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
	86	#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
	87	(nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
	88	(nlh)->nlmsg_len <= (len))
	89	#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
	90
	91	#define NLMSG_NOOP 0x1 /* Nothing. */
	92	#define NLMSG_ERROR 0x2 /* Error */
	93	#define NLMSG_DONE 0x3 /* End of a dump */
	94	#define NLMSG_OVERRUN 0x4 /* Data lost */
	95
	96	#define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
	97
	98	struct nlmsgerr {
	99	int error;
	100	struct nlmsghdr msg;
	101	};
	102
	103	#define NETLINK_ADD_MEMBERSHIP 1
	104	#define NETLINK_DROP_MEMBERSHIP 2
	105	#define NETLINK_PKTINFO 3
	106	#define NETLINK_BROADCAST_ERROR 4
	107	#define NETLINK_NO_ENOBUFS 5
	108
	109	struct nl_pktinfo {
	110	__u32 group;
	111	};
	112
	113	#define NET_MAJOR 36 /* Major 36 is reserved for networking */
	114
	115	enum {
	116	NETLINK_UNCONNECTED = 0,
	117	NETLINK_CONNECTED,
	118	};
	119
	120	/*
	121	* <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
	122	* +---------------------+- - -+- - - - - - - - - -+- - -+
	123	* \| Header \| Pad \| Payload \| Pad \|
	124	* \| (struct nlattr) \| ing \| \| ing \|
	125	* +---------------------+- - -+- - - - - - - - - -+- - -+
	126	* <-------------- nlattr->nla_len -------------->
	127	*/
	128
	129	struct nlattr {
	130	__u16 nla_len;
	131	__u16 nla_type;
	132	};
	133
	134	/*
	135	* nla_type (16 bits)
	136	* +---+---+-------------------------------+
	137	* \| N \| O \| Attribute Type \|
	138	* +---+---+-------------------------------+
	139	* N := Carries nested attributes
	140	* O := Payload stored in network byte order
	141	*
	142	* Note: The N and O flag are mutually exclusive.
	143	*/
	144	#define NLA_F_NESTED (1 << 15)
	145	#define NLA_F_NET_BYTEORDER (1 << 14)
	146	#define NLA_TYPE_MASK ~(NLA_F_NESTED \| NLA_F_NET_BYTEORDER)
	147
	148	#define NLA_ALIGNTO 4
	149	#define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
	150	#define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
	151
	152	#ifdef __KERNEL__
	153
	154	#include <linux/capability.h>
	155	#include <linux/skbuff.h>
	156	#include <linux/module.h>
	157	#include <net/scm.h>
	158
	159	struct net;
	160
	161	static inline struct nlmsghdr nlmsg_hdr(const struct sk_buff skb)
	162	{
	163	return (struct nlmsghdr *)skb->data;
	164	}
	165
	166	struct netlink_skb_parms {
	167	struct scm_creds creds; /* Skb credentials */
	168	__u32 portid;
	169	__u32 dst_group;
	170	struct sock *ssk;
	171	};
	172
	173	#define NETLINK_CB(skb) ((struct netlink_skb_parms)&((skb)->cb))
	174	#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
	175
	176
	177	extern void netlink_table_grab(void);
	178	extern void netlink_table_ungrab(void);
	179
	180	#define NL_CFG_F_NONROOT_RECV (1 << 0)
	181	#define NL_CFG_F_NONROOT_SEND (1 << 1)
	182
	183	/* optional Netlink kernel configuration parameters */
	184	struct netlink_kernel_cfg {
	185	unsigned int groups;
	186	void (input)(struct sk_buff skb);
	187	struct mutex *cb_mutex;
	188	void (*bind)(int group);
	189	unsigned int flags;
	190	};
	191
	192	extern struct sock __netlink_kernel_create(struct net net, int unit,
	193	struct module *module,
	194	struct netlink_kernel_cfg *cfg);
	195	static inline struct sock *
	196	netlink_kernel_create(struct net net, int unit, struct netlink_kernel_cfg cfg)
	197	{
	198	return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
	199	}
	200
	201	extern void netlink_kernel_release(struct sock *sk);
	202	extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
	203	extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
	204	extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
	205	extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
	206	extern void netlink_ack(struct sk_buff in_skb, struct nlmsghdr nlh, int err);
	207	extern int netlink_has_listeners(struct sock *sk, unsigned int group);
	208	extern int netlink_unicast(struct sock ssk, struct sk_buff skb, __u32 portid, int nonblock);
	209	extern int netlink_broadcast(struct sock ssk, struct sk_buff skb, __u32 portid,
	210	__u32 group, gfp_t allocation);
	211	extern int netlink_broadcast_filtered(struct sock ssk, struct sk_buff skb,
	212	__u32 portid, __u32 group, gfp_t allocation,
	213	int (filter)(struct sock dsk, struct sk_buff skb, void data),
	214	void *filter_data);
	215	extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
	216	extern int netlink_register_notifier(struct notifier_block *nb);
	217	extern int netlink_unregister_notifier(struct notifier_block *nb);
	218
	219	/* finegrained unicast helpers: */
	220	struct sock netlink_getsockbyfilp(struct file filp);
	221	int netlink_attachskb(struct sock sk, struct sk_buff skb,
	222	long timeo, struct sock ssk);
	223	void netlink_detachskb(struct sock sk, struct sk_buff skb);
	224	int netlink_sendskb(struct sock sk, struct sk_buff skb);
	225
	226	/*
	227	* skb should fit one page. This choice is good for headerless malloc.
	228	* But we should limit to 8K so that userspace does not have to
	229	* use enormous buffer sizes on recvmsg() calls just to avoid
	230	* MSG_TRUNC when PAGE_SIZE is very large.
	231	*/
	232	#if PAGE_SIZE < 8192UL
	233	#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
	234	#else
	235	#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
	236	#endif
	237
	238	#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
	239
	240
	241	struct netlink_callback {
	242	struct sk_buff *skb;
	243	const struct nlmsghdr *nlh;
	244	int (dump)(struct sk_buff skb,
	245	struct netlink_callback *cb);
	246	int (done)(struct netlink_callback cb);
	247	void *data;
	248	u16 family;
	249	u16 min_dump_alloc;
	250	unsigned int prev_seq, seq;
	251	long args[6];
	252	};
	253
	254	struct netlink_notify {
	255	struct net *net;
	256	int portid;
	257	int protocol;
	258	};
	259
	260	struct nlmsghdr *
	261	__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);
	262
	263	struct netlink_dump_control {
	264	int (dump)(struct sk_buff skb, struct netlink_callback *);
	265	int (done)(struct netlink_callback);
	266	void *data;
	267	u16 min_dump_alloc;
	268	};
	269
	270	extern int netlink_dump_start(struct sock ssk, struct sk_buff skb,
	271	const struct nlmsghdr *nlh,
	272	struct netlink_dump_control *control);
	273
	274	#endif /* __KERNEL__ */
	275
	276	#endif /* __LINUX_NETLINK_H */