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
32 struct 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
39 struct 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
95 struct 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
106 struct nl_pktinfo {
107 __u32 group;
108 };
109
110 #define NET_MAJOR 36 /* Major 36 is reserved for networking */
111
112 enum {
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
126 struct 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
154 struct net;
155
nlmsg_hdr(const struct sk_buff * skb)156 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
157 {
158 return (struct nlmsghdr *)skb->data;
159 }
160
161 struct 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
171 extern void netlink_table_grab(void);
172 extern void netlink_table_ungrab(void);
173
174 extern 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);
179 extern void netlink_kernel_release(struct sock *sk);
180 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
181 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
182 extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
183 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
184 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
185 extern int netlink_has_listeners(struct sock *sk, unsigned int group);
186 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
187 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
188 __u32 group, gfp_t allocation);
189 extern 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);
193 extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
194 extern int netlink_register_notifier(struct notifier_block *nb);
195 extern int netlink_unregister_notifier(struct notifier_block *nb);
196
197 /* finegrained unicast helpers: */
198 struct sock *netlink_getsockbyfilp(struct file *filp);
199 int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
200 long *timeo, struct sock *ssk);
201 void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
202 int 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
219 struct 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
229 struct netlink_notify {
230 struct net *net;
231 int pid;
232 int protocol;
233 };
234
235 static __inline__ struct nlmsghdr *
__nlmsg_put(struct sk_buff * skb,u32 pid,u32 seq,int type,int len,int flags)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
260 extern 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
268 extern void netlink_set_nonroot(int protocol, unsigned flag);
269
270 #endif /* __KERNEL__ */
271
272 #endif /* __LINUX_NETLINK_H */
273