xref: /linux-6.15/include/uapi/linux/netlink.h (revision bbb03029)
1 #ifndef _UAPI__LINUX_NETLINK_H
2 #define _UAPI__LINUX_NETLINK_H
3 
4 #include <linux/kernel.h>
5 #include <linux/socket.h> /* for __kernel_sa_family_t */
6 #include <linux/types.h>
7 
8 #define NETLINK_ROUTE		0	/* Routing/device hook				*/
9 #define NETLINK_UNUSED		1	/* Unused number				*/
10 #define NETLINK_USERSOCK	2	/* Reserved for user mode socket protocols 	*/
11 #define NETLINK_FIREWALL	3	/* Unused number, formerly ip_queue		*/
12 #define NETLINK_SOCK_DIAG	4	/* socket monitoring				*/
13 #define NETLINK_NFLOG		5	/* netfilter/iptables ULOG */
14 #define NETLINK_XFRM		6	/* ipsec */
15 #define NETLINK_SELINUX		7	/* SELinux event notifications */
16 #define NETLINK_ISCSI		8	/* Open-iSCSI */
17 #define NETLINK_AUDIT		9	/* auditing */
18 #define NETLINK_FIB_LOOKUP	10
19 #define NETLINK_CONNECTOR	11
20 #define NETLINK_NETFILTER	12	/* netfilter subsystem */
21 #define NETLINK_IP6_FW		13
22 #define NETLINK_DNRTMSG		14	/* DECnet routing messages */
23 #define NETLINK_KOBJECT_UEVENT	15	/* Kernel messages to userspace */
24 #define NETLINK_GENERIC		16
25 /* leave room for NETLINK_DM (DM Events) */
26 #define NETLINK_SCSITRANSPORT	18	/* SCSI Transports */
27 #define NETLINK_ECRYPTFS	19
28 #define NETLINK_RDMA		20
29 #define NETLINK_CRYPTO		21	/* Crypto layer */
30 #define NETLINK_SMC		22	/* SMC monitoring */
31 
32 #define NETLINK_INET_DIAG	NETLINK_SOCK_DIAG
33 
34 #define MAX_LINKS 32
35 
36 struct sockaddr_nl {
37 	__kernel_sa_family_t	nl_family;	/* AF_NETLINK	*/
38 	unsigned short	nl_pad;		/* zero		*/
39 	__u32		nl_pid;		/* port ID	*/
40        	__u32		nl_groups;	/* multicast groups mask */
41 };
42 
43 struct nlmsghdr {
44 	__u32		nlmsg_len;	/* Length of message including header */
45 	__u16		nlmsg_type;	/* Message content */
46 	__u16		nlmsg_flags;	/* Additional flags */
47 	__u32		nlmsg_seq;	/* Sequence number */
48 	__u32		nlmsg_pid;	/* Sending process port ID */
49 };
50 
51 /* Flags values */
52 
53 #define NLM_F_REQUEST		0x01	/* It is request message. 	*/
54 #define NLM_F_MULTI		0x02	/* Multipart message, terminated by NLMSG_DONE */
55 #define NLM_F_ACK		0x04	/* Reply with ack, with zero or error code */
56 #define NLM_F_ECHO		0x08	/* Echo this request 		*/
57 #define NLM_F_DUMP_INTR		0x10	/* Dump was inconsistent due to sequence change */
58 #define NLM_F_DUMP_FILTERED	0x20	/* Dump was filtered as requested */
59 
60 /* Modifiers to GET request */
61 #define NLM_F_ROOT	0x100	/* specify tree	root	*/
62 #define NLM_F_MATCH	0x200	/* return all matching	*/
63 #define NLM_F_ATOMIC	0x400	/* atomic GET		*/
64 #define NLM_F_DUMP	(NLM_F_ROOT|NLM_F_MATCH)
65 
66 /* Modifiers to NEW request */
67 #define NLM_F_REPLACE	0x100	/* Override existing		*/
68 #define NLM_F_EXCL	0x200	/* Do not touch, if it exists	*/
69 #define NLM_F_CREATE	0x400	/* Create, if it does not exist	*/
70 #define NLM_F_APPEND	0x800	/* Add to end of list		*/
71 
72 /* Flags for ACK message */
73 #define NLM_F_CAPPED	0x100	/* request was capped */
74 #define NLM_F_ACK_TLVS	0x200	/* extended ACK TVLs were included */
75 
76 /*
77    4.4BSD ADD		NLM_F_CREATE|NLM_F_EXCL
78    4.4BSD CHANGE	NLM_F_REPLACE
79 
80    True CHANGE		NLM_F_CREATE|NLM_F_REPLACE
81    Append		NLM_F_CREATE
82    Check		NLM_F_EXCL
83  */
84 
85 #define NLMSG_ALIGNTO	4U
86 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
87 #define NLMSG_HDRLEN	 ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
88 #define NLMSG_LENGTH(len) ((len) + NLMSG_HDRLEN)
89 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
90 #define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
91 #define NLMSG_NEXT(nlh,len)	 ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
92 				  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
93 #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
94 			   (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
95 			   (nlh)->nlmsg_len <= (len))
96 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
97 
98 #define NLMSG_NOOP		0x1	/* Nothing.		*/
99 #define NLMSG_ERROR		0x2	/* Error		*/
100 #define NLMSG_DONE		0x3	/* End of a dump	*/
101 #define NLMSG_OVERRUN		0x4	/* Data lost		*/
102 
103 #define NLMSG_MIN_TYPE		0x10	/* < 0x10: reserved control messages */
104 
105 struct nlmsgerr {
106 	int		error;
107 	struct nlmsghdr msg;
108 	/*
109 	 * followed by the message contents unless NETLINK_CAP_ACK was set
110 	 * or the ACK indicates success (error == 0)
111 	 * message length is aligned with NLMSG_ALIGN()
112 	 */
113 	/*
114 	 * followed by TLVs defined in enum nlmsgerr_attrs
115 	 * if NETLINK_EXT_ACK was set
116 	 */
117 };
118 
119 /**
120  * enum nlmsgerr_attrs - nlmsgerr attributes
121  * @NLMSGERR_ATTR_UNUSED: unused
122  * @NLMSGERR_ATTR_MSG: error message string (string)
123  * @NLMSGERR_ATTR_OFFS: offset of the invalid attribute in the original
124  *	 message, counting from the beginning of the header (u32)
125  * @NLMSGERR_ATTR_COOKIE: arbitrary subsystem specific cookie to
126  *	be used - in the success case - to identify a created
127  *	object or operation or similar (binary)
128  * @__NLMSGERR_ATTR_MAX: number of attributes
129  * @NLMSGERR_ATTR_MAX: highest attribute number
130  */
131 enum nlmsgerr_attrs {
132 	NLMSGERR_ATTR_UNUSED,
133 	NLMSGERR_ATTR_MSG,
134 	NLMSGERR_ATTR_OFFS,
135 	NLMSGERR_ATTR_COOKIE,
136 
137 	__NLMSGERR_ATTR_MAX,
138 	NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
139 };
140 
141 #define NETLINK_ADD_MEMBERSHIP		1
142 #define NETLINK_DROP_MEMBERSHIP		2
143 #define NETLINK_PKTINFO			3
144 #define NETLINK_BROADCAST_ERROR		4
145 #define NETLINK_NO_ENOBUFS		5
146 #ifndef __KERNEL__
147 #define NETLINK_RX_RING			6
148 #define NETLINK_TX_RING			7
149 #endif
150 #define NETLINK_LISTEN_ALL_NSID		8
151 #define NETLINK_LIST_MEMBERSHIPS	9
152 #define NETLINK_CAP_ACK			10
153 #define NETLINK_EXT_ACK			11
154 
155 struct nl_pktinfo {
156 	__u32	group;
157 };
158 
159 struct nl_mmap_req {
160 	unsigned int	nm_block_size;
161 	unsigned int	nm_block_nr;
162 	unsigned int	nm_frame_size;
163 	unsigned int	nm_frame_nr;
164 };
165 
166 struct nl_mmap_hdr {
167 	unsigned int	nm_status;
168 	unsigned int	nm_len;
169 	__u32		nm_group;
170 	/* credentials */
171 	__u32		nm_pid;
172 	__u32		nm_uid;
173 	__u32		nm_gid;
174 };
175 
176 #ifndef __KERNEL__
177 enum nl_mmap_status {
178 	NL_MMAP_STATUS_UNUSED,
179 	NL_MMAP_STATUS_RESERVED,
180 	NL_MMAP_STATUS_VALID,
181 	NL_MMAP_STATUS_COPY,
182 	NL_MMAP_STATUS_SKIP,
183 };
184 
185 #define NL_MMAP_MSG_ALIGNMENT		NLMSG_ALIGNTO
186 #define NL_MMAP_MSG_ALIGN(sz)		__ALIGN_KERNEL(sz, NL_MMAP_MSG_ALIGNMENT)
187 #define NL_MMAP_HDRLEN			NL_MMAP_MSG_ALIGN(sizeof(struct nl_mmap_hdr))
188 #endif
189 
190 #define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/
191 
192 enum {
193 	NETLINK_UNCONNECTED = 0,
194 	NETLINK_CONNECTED,
195 };
196 
197 /*
198  *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
199  * +---------------------+- - -+- - - - - - - - - -+- - -+
200  * |        Header       | Pad |     Payload       | Pad |
201  * |   (struct nlattr)   | ing |                   | ing |
202  * +---------------------+- - -+- - - - - - - - - -+- - -+
203  *  <-------------- nlattr->nla_len -------------->
204  */
205 
206 struct nlattr {
207 	__u16           nla_len;
208 	__u16           nla_type;
209 };
210 
211 /*
212  * nla_type (16 bits)
213  * +---+---+-------------------------------+
214  * | N | O | Attribute Type                |
215  * +---+---+-------------------------------+
216  * N := Carries nested attributes
217  * O := Payload stored in network byte order
218  *
219  * Note: The N and O flag are mutually exclusive.
220  */
221 #define NLA_F_NESTED		(1 << 15)
222 #define NLA_F_NET_BYTEORDER	(1 << 14)
223 #define NLA_TYPE_MASK		~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
224 
225 #define NLA_ALIGNTO		4
226 #define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
227 #define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))
228 
229 /* Generic 32 bitflags attribute content sent to the kernel.
230  *
231  * The value is a bitmap that defines the values being set
232  * The selector is a bitmask that defines which value is legit
233  *
234  * Examples:
235  *  value = 0x0, and selector = 0x1
236  *  implies we are selecting bit 1 and we want to set its value to 0.
237  *
238  *  value = 0x2, and selector = 0x2
239  *  implies we are selecting bit 2 and we want to set its value to 1.
240  *
241  */
242 struct nla_bitfield32 {
243 	__u32 value;
244 	__u32 selector;
245 };
246 
247 #endif /* _UAPI__LINUX_NETLINK_H */
248