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 /* Firewalling hook */
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/export.h>
157
158 struct net;
159
nlmsg_hdr(const struct sk_buff * skb)160 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
161 {
162 return (struct nlmsghdr *)skb->data;
163 }
164
165 struct netlink_skb_parms {
166 struct ucred creds; /* Skb credentials */
167 __u32 pid;
168 __u32 dst_group;
169 };
170
171 #define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
172 #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
173
174
175 extern void netlink_table_grab(void);
176 extern void netlink_table_ungrab(void);
177
178 extern struct sock *netlink_kernel_create(struct net *net,
179 int unit,unsigned int groups,
180 void (*input)(struct sk_buff *skb),
181 struct mutex *cb_mutex,
182 struct module *module);
183 extern void netlink_kernel_release(struct sock *sk);
184 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
185 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
186 extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
187 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
188 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
189 extern int netlink_has_listeners(struct sock *sk, unsigned int group);
190 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
191 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
192 __u32 group, gfp_t allocation);
193 extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
194 __u32 pid, __u32 group, gfp_t allocation,
195 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
196 void *filter_data);
197 extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
198 extern int netlink_register_notifier(struct notifier_block *nb);
199 extern int netlink_unregister_notifier(struct notifier_block *nb);
200
201 /* finegrained unicast helpers: */
202 struct sock *netlink_getsockbyfilp(struct file *filp);
203 int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
204 long *timeo, struct sock *ssk);
205 void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
206 int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
207
208 /*
209 * skb should fit one page. This choice is good for headerless malloc.
210 * But we should limit to 8K so that userspace does not have to
211 * use enormous buffer sizes on recvmsg() calls just to avoid
212 * MSG_TRUNC when PAGE_SIZE is very large.
213 */
214 #if PAGE_SIZE < 8192UL
215 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
216 #else
217 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
218 #endif
219
220 #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
221
222
223 struct netlink_callback {
224 struct sk_buff *skb;
225 const struct nlmsghdr *nlh;
226 int (*dump)(struct sk_buff * skb,
227 struct netlink_callback *cb);
228 int (*done)(struct netlink_callback *cb);
229 void *data;
230 /* the module that dump function belong to */
231 struct module *module;
232 u16 family;
233 u16 min_dump_alloc;
234 unsigned int prev_seq, seq;
235 long args[6];
236 };
237
238 struct netlink_notify {
239 struct net *net;
240 int pid;
241 int protocol;
242 };
243
244 struct nlmsghdr *
245 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags);
246
247 #define NLMSG_NEW(skb, pid, seq, type, len, flags) \
248 ({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
249 goto nlmsg_failure; \
250 __nlmsg_put(skb, pid, seq, type, len, flags); })
251
252 #define NLMSG_PUT(skb, pid, seq, type, len) \
253 NLMSG_NEW(skb, pid, seq, type, len, 0)
254
255 struct netlink_dump_control {
256 int (*dump)(struct sk_buff *skb, struct netlink_callback *);
257 int (*done)(struct netlink_callback *);
258 void *data;
259 struct module *module;
260 u16 min_dump_alloc;
261 };
262
263 extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
264 const struct nlmsghdr *nlh,
265 struct netlink_dump_control *control);
netlink_dump_start(struct sock * ssk,struct sk_buff * skb,const struct nlmsghdr * nlh,struct netlink_dump_control * control)266 static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
267 const struct nlmsghdr *nlh,
268 struct netlink_dump_control *control)
269 {
270 if (!control->module)
271 control->module = THIS_MODULE;
272
273 return __netlink_dump_start(ssk, skb, nlh, control);
274 }
275
276
277 #define NL_NONROOT_RECV 0x1
278 #define NL_NONROOT_SEND 0x2
279 extern void netlink_set_nonroot(int protocol, unsigned flag);
280
281 #endif /* __KERNEL__ */
282
283 #endif /* __LINUX_NETLINK_H */
284