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
28 #define MAX_LINKS 32
29
30 struct net;
31
32 struct sockaddr_nl
33 {
34 sa_family_t nl_family; /* AF_NETLINK */
35 unsigned short nl_pad; /* zero */
36 __u32 nl_pid; /* port ID */
37 __u32 nl_groups; /* multicast groups mask */
38 };
39
40 struct nlmsghdr
41 {
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
56 /* Modifiers to GET request */
57 #define NLM_F_ROOT 0x100 /* specify tree root */
58 #define NLM_F_MATCH 0x200 /* return all matching */
59 #define NLM_F_ATOMIC 0x400 /* atomic GET */
60 #define NLM_F_DUMP (NLM_F_ROOT|NLM_F_MATCH)
61
62 /* Modifiers to NEW request */
63 #define NLM_F_REPLACE 0x100 /* Override existing */
64 #define NLM_F_EXCL 0x200 /* Do not touch, if it exists */
65 #define NLM_F_CREATE 0x400 /* Create, if it does not exist */
66 #define NLM_F_APPEND 0x800 /* Add to end of list */
67
68 /*
69 4.4BSD ADD NLM_F_CREATE|NLM_F_EXCL
70 4.4BSD CHANGE NLM_F_REPLACE
71
72 True CHANGE NLM_F_CREATE|NLM_F_REPLACE
73 Append NLM_F_CREATE
74 Check NLM_F_EXCL
75 */
76
77 #define NLMSG_ALIGNTO 4
78 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
79 #define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
80 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
81 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
82 #define NLMSG_DATA(nlh) ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
83 #define NLMSG_NEXT(nlh,len) ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
84 (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
85 #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
86 (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
87 (nlh)->nlmsg_len <= (len))
88 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
89
90 #define NLMSG_NOOP 0x1 /* Nothing. */
91 #define NLMSG_ERROR 0x2 /* Error */
92 #define NLMSG_DONE 0x3 /* End of a dump */
93 #define NLMSG_OVERRUN 0x4 /* Data lost */
94
95 #define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
96
97 struct nlmsgerr
98 {
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 {
111 __u32 group;
112 };
113
114 #define NET_MAJOR 36 /* Major 36 is reserved for networking */
115
116 enum {
117 NETLINK_UNCONNECTED = 0,
118 NETLINK_CONNECTED,
119 };
120
121 /*
122 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
123 * +---------------------+- - -+- - - - - - - - - -+- - -+
124 * | Header | Pad | Payload | Pad |
125 * | (struct nlattr) | ing | | ing |
126 * +---------------------+- - -+- - - - - - - - - -+- - -+
127 * <-------------- nlattr->nla_len -------------->
128 */
129
130 struct nlattr
131 {
132 __u16 nla_len;
133 __u16 nla_type;
134 };
135
136 /*
137 * nla_type (16 bits)
138 * +---+---+-------------------------------+
139 * | N | O | Attribute Type |
140 * +---+---+-------------------------------+
141 * N := Carries nested attributes
142 * O := Payload stored in network byte order
143 *
144 * Note: The N and O flag are mutually exclusive.
145 */
146 #define NLA_F_NESTED (1 << 15)
147 #define NLA_F_NET_BYTEORDER (1 << 14)
148 #define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
149
150 #define NLA_ALIGNTO 4
151 #define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
152 #define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
153
154 #ifdef __KERNEL__
155
156 #include <linux/capability.h>
157 #include <linux/skbuff.h>
158
nlmsg_hdr(const struct sk_buff * skb)159 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
160 {
161 return (struct nlmsghdr *)skb->data;
162 }
163
164 struct netlink_skb_parms
165 {
166 struct ucred creds; /* Skb credentials */
167 __u32 pid;
168 __u32 dst_group;
169 kernel_cap_t eff_cap;
170 __u32 loginuid; /* Login (audit) uid */
171 __u32 sessionid; /* Session id (audit) */
172 __u32 sid; /* SELinux security id */
173 };
174
175 #define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
176 #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
177
178
179 extern void netlink_table_grab(void);
180 extern void netlink_table_ungrab(void);
181
182 extern struct sock *netlink_kernel_create(struct net *net,
183 int unit,unsigned int groups,
184 void (*input)(struct sk_buff *skb),
185 struct mutex *cb_mutex,
186 struct module *module);
187 extern void netlink_kernel_release(struct sock *sk);
188 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
189 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
190 extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
191 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
192 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
193 extern int netlink_has_listeners(struct sock *sk, unsigned int group);
194 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
195 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
196 __u32 group, gfp_t allocation);
197 extern void 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 {
225 struct sk_buff *skb;
226 const struct nlmsghdr *nlh;
227 int (*dump)(struct sk_buff * skb,
228 struct netlink_callback *cb);
229 int (*done)(struct netlink_callback *cb);
230 int family;
231 long args[6];
232 };
233
234 struct netlink_notify
235 {
236 struct net *net;
237 int pid;
238 int protocol;
239 };
240
241 static __inline__ struct nlmsghdr *
__nlmsg_put(struct sk_buff * skb,u32 pid,u32 seq,int type,int len,int flags)242 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
243 {
244 struct nlmsghdr *nlh;
245 int size = NLMSG_LENGTH(len);
246
247 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
248 nlh->nlmsg_type = type;
249 nlh->nlmsg_len = size;
250 nlh->nlmsg_flags = flags;
251 nlh->nlmsg_pid = pid;
252 nlh->nlmsg_seq = seq;
253 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
254 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
255 return nlh;
256 }
257
258 #define NLMSG_NEW(skb, pid, seq, type, len, flags) \
259 ({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
260 goto nlmsg_failure; \
261 __nlmsg_put(skb, pid, seq, type, len, flags); })
262
263 #define NLMSG_PUT(skb, pid, seq, type, len) \
264 NLMSG_NEW(skb, pid, seq, type, len, 0)
265
266 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
267 const struct nlmsghdr *nlh,
268 int (*dump)(struct sk_buff *skb, struct netlink_callback*),
269 int (*done)(struct netlink_callback*));
270
271
272 #define NL_NONROOT_RECV 0x1
273 #define NL_NONROOT_SEND 0x2
274 extern void netlink_set_nonroot(int protocol, unsigned flag);
275
276 #endif /* __KERNEL__ */
277
278 #endif /* __LINUX_NETLINK_H */
279