1 #ifndef __LINUX_NETLINK_H
2 #define __LINUX_NETLINK_H
3 
4 #define NETLINK_ROUTE		0	/* Routing/device hook				*/
5 #define NETLINK_SKIP		1	/* Reserved for ENskip  			*/
6 #define NETLINK_USERSOCK	2	/* Reserved for user mode socket protocols 	*/
7 #define NETLINK_FIREWALL	3	/* Firewalling hook				*/
8 #define NETLINK_TCPDIAG		4	/* TCP socket monitoring			*/
9 #define NETLINK_NFLOG		5	/* netfilter/iptables ULOG */
10 #define NETLINK_ARPD		8
11 #define NETLINK_ROUTE6		11	/* af_inet6 route comm channel */
12 #define NETLINK_IP6_FW		13
13 #define NETLINK_DNRTMSG		14	/* DECnet routing messages */
14 #define NETLINK_TAPBASE		16	/* 16 to 31 are ethertap */
15 
16 #define MAX_LINKS 32
17 
18 struct sockaddr_nl
19 {
20 	sa_family_t	nl_family;	/* AF_NETLINK	*/
21 	unsigned short	nl_pad;		/* zero		*/
22 	__u32		nl_pid;		/* process pid	*/
23        	__u32		nl_groups;	/* multicast groups mask */
24 };
25 
26 struct nlmsghdr
27 {
28 	__u32		nlmsg_len;	/* Length of message including header */
29 	__u16		nlmsg_type;	/* Message content */
30 	__u16		nlmsg_flags;	/* Additional flags */
31 	__u32		nlmsg_seq;	/* Sequence number */
32 	__u32		nlmsg_pid;	/* Sending process PID */
33 };
34 
35 /* Flags values */
36 
37 #define NLM_F_REQUEST		1	/* It is request message. 	*/
38 #define NLM_F_MULTI		2	/* Multipart message, terminated by NLMSG_DONE */
39 #define NLM_F_ACK		4	/* Reply with ack, with zero or error code */
40 #define NLM_F_ECHO		8	/* Echo this request 		*/
41 
42 /* Modifiers to GET request */
43 #define NLM_F_ROOT	0x100	/* specify tree	root	*/
44 #define NLM_F_MATCH	0x200	/* return all matching	*/
45 #define NLM_F_ATOMIC	0x400	/* atomic GET		*/
46 #define NLM_F_DUMP	(NLM_F_ROOT|NLM_F_MATCH)
47 
48 /* Modifiers to NEW request */
49 #define NLM_F_REPLACE	0x100	/* Override existing		*/
50 #define NLM_F_EXCL	0x200	/* Do not touch, if it exists	*/
51 #define NLM_F_CREATE	0x400	/* Create, if it does not exist	*/
52 #define NLM_F_APPEND	0x800	/* Add to end of list		*/
53 
54 /*
55    4.4BSD ADD		NLM_F_CREATE|NLM_F_EXCL
56    4.4BSD CHANGE	NLM_F_REPLACE
57 
58    True CHANGE		NLM_F_CREATE|NLM_F_REPLACE
59    Append		NLM_F_CREATE
60    Check		NLM_F_EXCL
61  */
62 
63 #define NLMSG_ALIGNTO	4
64 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
65 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(sizeof(struct nlmsghdr)))
66 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
67 #define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
68 #define NLMSG_NEXT(nlh,len)	 ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
69 				  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
70 #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
71 			   (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
72 			   (nlh)->nlmsg_len <= (len))
73 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
74 
75 #define NLMSG_NOOP		0x1	/* Nothing.		*/
76 #define NLMSG_ERROR		0x2	/* Error		*/
77 #define NLMSG_DONE		0x3	/* End of a dump	*/
78 #define NLMSG_OVERRUN		0x4	/* Data lost		*/
79 
80 struct nlmsgerr
81 {
82 	int		error;
83 	struct nlmsghdr msg;
84 };
85 
86 #define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/
87 
88 #ifdef __KERNEL__
89 
90 struct netlink_skb_parms
91 {
92 	struct ucred		creds;		/* Skb credentials	*/
93 	__u32			pid;
94 	__u32			groups;
95 	__u32			dst_pid;
96 	__u32			dst_groups;
97 	kernel_cap_t		eff_cap;
98 };
99 
100 #define NETLINK_CB(skb)		(*(struct netlink_skb_parms*)&((skb)->cb))
101 #define NETLINK_CREDS(skb)	(&NETLINK_CB((skb)).creds)
102 
103 
104 extern int netlink_attach(int unit, int (*function)(int,struct sk_buff *skb));
105 extern void netlink_detach(int unit);
106 extern int netlink_post(int unit, struct sk_buff *skb);
107 extern int init_netlink(void);
108 extern struct sock *netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len));
109 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
110 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
111 extern void netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
112 			      __u32 group, int allocation);
113 extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
114 extern int netlink_register_notifier(struct notifier_block *nb);
115 extern int netlink_unregister_notifier(struct notifier_block *nb);
116 extern int netlink_proto_init(void);
117 
118 /*
119  *	skb should fit one page. This choice is good for headerless malloc.
120  */
121 #define NLMSG_GOODORDER 0
122 #define NLMSG_GOODSIZE (SKB_MAX_ORDER(0, NLMSG_GOODORDER))
123 
124 
125 struct netlink_callback
126 {
127 	struct sk_buff	*skb;
128 	struct nlmsghdr	*nlh;
129 	int		(*dump)(struct sk_buff * skb, struct netlink_callback *cb);
130 	int		(*done)(struct netlink_callback *cb);
131 	int		family;
132 	long		args[4];
133 };
134 
135 struct netlink_notify
136 {
137 	int pid;
138 	int protocol;
139 };
140 
141 static __inline__ struct nlmsghdr *
__nlmsg_put(struct sk_buff * skb,u32 pid,u32 seq,int type,int len)142 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len)
143 {
144 	struct nlmsghdr *nlh;
145 	int size = NLMSG_LENGTH(len);
146 
147 	nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
148 	nlh->nlmsg_type = type;
149 	nlh->nlmsg_len = size;
150 	nlh->nlmsg_flags = 0;
151 	nlh->nlmsg_pid = pid;
152 	nlh->nlmsg_seq = seq;
153 	memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
154 	return nlh;
155 }
156 
157 #define NLMSG_PUT(skb, pid, seq, type, len) \
158 ({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) goto nlmsg_failure; \
159    __nlmsg_put(skb, pid, seq, type, len); })
160 
161 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
162 			      struct nlmsghdr *nlh,
163 			      int (*dump)(struct sk_buff *skb, struct netlink_callback*),
164 			      int (*done)(struct netlink_callback*));
165 
166 #define NL_NONROOT_RECV 0x1
167 #define NL_NONROOT_SEND 0x2
168 extern void netlink_set_nonroot(int protocol, unsigned flag);
169 
170 
171 #endif /* __KERNEL__ */
172 
173 #endif	/* __LINUX_NETLINK_H */
174