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