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
107 struct nl_pktinfo
108 {
109 __u32 group;
110 };
111
112 #define NET_MAJOR 36 /* Major 36 is reserved for networking */
113
114 enum {
115 NETLINK_UNCONNECTED = 0,
116 NETLINK_CONNECTED,
117 };
118
119 /*
120 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
121 * +---------------------+- - -+- - - - - - - - - -+- - -+
122 * | Header | Pad | Payload | Pad |
123 * | (struct nlattr) | ing | | ing |
124 * +---------------------+- - -+- - - - - - - - - -+- - -+
125 * <-------------- nlattr->nla_len -------------->
126 */
127
128 struct nlattr
129 {
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
nlmsg_hdr(const struct sk_buff * skb)157 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
158 {
159 return (struct nlmsghdr *)skb->data;
160 }
161
162 struct netlink_skb_parms
163 {
164 struct ucred creds; /* Skb credentials */
165 __u32 pid;
166 __u32 dst_group;
167 kernel_cap_t eff_cap;
168 __u32 loginuid; /* Login (audit) uid */
169 __u32 sessionid; /* Session id (audit) */
170 __u32 sid; /* SELinux security id */
171 };
172
173 #define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
174 #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
175
176
177 extern struct sock *netlink_kernel_create(struct net *net,
178 int unit,unsigned int groups,
179 void (*input)(struct sk_buff *skb),
180 struct mutex *cb_mutex,
181 struct module *module);
182 extern void netlink_kernel_release(struct sock *sk);
183 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
184 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
185 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
186 extern int netlink_has_listeners(struct sock *sk, unsigned int group);
187 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
188 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
189 __u32 group, gfp_t allocation);
190 extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
191 extern int netlink_register_notifier(struct notifier_block *nb);
192 extern int netlink_unregister_notifier(struct notifier_block *nb);
193
194 /* finegrained unicast helpers: */
195 struct sock *netlink_getsockbyfilp(struct file *filp);
196 int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
197 long *timeo, struct sock *ssk);
198 void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
199 int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
200
201 /*
202 * skb should fit one page. This choice is good for headerless malloc.
203 * But we should limit to 8K so that userspace does not have to
204 * use enormous buffer sizes on recvmsg() calls just to avoid
205 * MSG_TRUNC when PAGE_SIZE is very large.
206 */
207 #if PAGE_SIZE < 8192UL
208 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
209 #else
210 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
211 #endif
212
213 #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
214
215
216 struct netlink_callback
217 {
218 struct sk_buff *skb;
219 struct nlmsghdr *nlh;
220 int (*dump)(struct sk_buff * skb, struct netlink_callback *cb);
221 int (*done)(struct netlink_callback *cb);
222 int family;
223 long args[6];
224 };
225
226 struct netlink_notify
227 {
228 struct net *net;
229 int pid;
230 int protocol;
231 };
232
233 static __inline__ struct nlmsghdr *
__nlmsg_put(struct sk_buff * skb,u32 pid,u32 seq,int type,int len,int flags)234 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
235 {
236 struct nlmsghdr *nlh;
237 int size = NLMSG_LENGTH(len);
238
239 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
240 nlh->nlmsg_type = type;
241 nlh->nlmsg_len = size;
242 nlh->nlmsg_flags = flags;
243 nlh->nlmsg_pid = pid;
244 nlh->nlmsg_seq = seq;
245 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
246 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
247 return nlh;
248 }
249
250 #define NLMSG_NEW(skb, pid, seq, type, len, flags) \
251 ({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
252 goto nlmsg_failure; \
253 __nlmsg_put(skb, pid, seq, type, len, flags); })
254
255 #define NLMSG_PUT(skb, pid, seq, type, len) \
256 NLMSG_NEW(skb, pid, seq, type, len, 0)
257
258 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
259 struct nlmsghdr *nlh,
260 int (*dump)(struct sk_buff *skb, struct netlink_callback*),
261 int (*done)(struct netlink_callback*));
262
263
264 #define NL_NONROOT_RECV 0x1
265 #define NL_NONROOT_SEND 0x2
266 extern void netlink_set_nonroot(int protocol, unsigned flag);
267
268 #endif /* __KERNEL__ */
269
270 #endif /* __LINUX_NETLINK_H */
271