1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef __LINUX_NETLINK_H
3#define __LINUX_NETLINK_H
4
5#include <linux/const.h>
6#include <linux/socket.h> /* for __kernel_sa_family_t */
7#include <linux/types.h>
8
9#define NETLINK_ROUTE 0 /* Routing/device hook */
10#define NETLINK_UNUSED 1 /* Unused number */
11#define NETLINK_USERSOCK 2 /* Reserved for user mode socket protocols */
12#define NETLINK_FIREWALL 3 /* Unused number, formerly ip_queue */
13#define NETLINK_SOCK_DIAG 4 /* socket monitoring */
14#define NETLINK_NFLOG 5 /* netfilter/iptables ULOG */
15#define NETLINK_XFRM 6 /* ipsec */
16#define NETLINK_SELINUX 7 /* SELinux event notifications */
17#define NETLINK_ISCSI 8 /* Open-iSCSI */
18#define NETLINK_AUDIT 9 /* auditing */
19#define NETLINK_FIB_LOOKUP 10
20#define NETLINK_CONNECTOR 11
21#define NETLINK_NETFILTER 12 /* netfilter subsystem */
22#define NETLINK_IP6_FW 13
23#define NETLINK_DNRTMSG 14 /* DECnet routing messages (obsolete) */
24#define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */
25#define NETLINK_GENERIC 16
26/* leave room for NETLINK_DM (DM Events) */
27#define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */
28#define NETLINK_ECRYPTFS 19
29#define NETLINK_RDMA 20
30#define NETLINK_CRYPTO 21 /* Crypto layer */
31#define NETLINK_SMC 22 /* SMC monitoring */
32
33#define NETLINK_INET_DIAG NETLINK_SOCK_DIAG
34
35#define MAX_LINKS 32
36
37struct sockaddr_nl {
38 __kernel_sa_family_t nl_family; /* AF_NETLINK */
39 unsigned short nl_pad; /* zero */
40 __u32 nl_pid; /* port ID */
41 __u32 nl_groups; /* multicast groups mask */
42};
43
44/**
45 * struct nlmsghdr - fixed format metadata header of Netlink messages
46 * @nlmsg_len: Length of message including header
47 * @nlmsg_type: Message content type
48 * @nlmsg_flags: Additional flags
49 * @nlmsg_seq: Sequence number
50 * @nlmsg_pid: Sending process port ID
51 */
52struct nlmsghdr {
53 __u32 nlmsg_len;
54 __u16 nlmsg_type;
55 __u16 nlmsg_flags;
56 __u32 nlmsg_seq;
57 __u32 nlmsg_pid;
58};
59
60/* Flags values */
61
62#define NLM_F_REQUEST 0x01 /* It is request message. */
63#define NLM_F_MULTI 0x02 /* Multipart message, terminated by NLMSG_DONE */
64#define NLM_F_ACK 0x04 /* Reply with ack, with zero or error code */
65#define NLM_F_ECHO 0x08 /* Receive resulting notifications */
66#define NLM_F_DUMP_INTR 0x10 /* Dump was inconsistent due to sequence change */
67#define NLM_F_DUMP_FILTERED 0x20 /* Dump was filtered as requested */
68
69/* Modifiers to GET request */
70#define NLM_F_ROOT 0x100 /* specify tree root */
71#define NLM_F_MATCH 0x200 /* return all matching */
72#define NLM_F_ATOMIC 0x400 /* atomic GET */
73#define NLM_F_DUMP (NLM_F_ROOT|NLM_F_MATCH)
74
75/* Modifiers to NEW request */
76#define NLM_F_REPLACE 0x100 /* Override existing */
77#define NLM_F_EXCL 0x200 /* Do not touch, if it exists */
78#define NLM_F_CREATE 0x400 /* Create, if it does not exist */
79#define NLM_F_APPEND 0x800 /* Add to end of list */
80
81/* Modifiers to DELETE request */
82#define NLM_F_NONREC 0x100 /* Do not delete recursively */
83#define NLM_F_BULK 0x200 /* Delete multiple objects */
84
85/* Flags for ACK message */
86#define NLM_F_CAPPED 0x100 /* request was capped */
87#define NLM_F_ACK_TLVS 0x200 /* extended ACK TVLs were included */
88
89/*
90 4.4BSD ADD NLM_F_CREATE|NLM_F_EXCL
91 4.4BSD CHANGE NLM_F_REPLACE
92
93 True CHANGE NLM_F_CREATE|NLM_F_REPLACE
94 Append NLM_F_CREATE
95 Check NLM_F_EXCL
96 */
97
98#define NLMSG_ALIGNTO 4U
99#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
100#define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
101#define NLMSG_LENGTH(len) ((len) + NLMSG_HDRLEN)
102#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
103#define NLMSG_DATA(nlh) ((void *)(((char *)nlh) + NLMSG_HDRLEN))
104#define NLMSG_NEXT(nlh,len) ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
105 (struct nlmsghdr *)(((char *)(nlh)) + \
106 NLMSG_ALIGN((nlh)->nlmsg_len)))
107#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
108 (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
109 (nlh)->nlmsg_len <= (len))
110#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
111
112#define NLMSG_NOOP 0x1 /* Nothing. */
113#define NLMSG_ERROR 0x2 /* Error */
114#define NLMSG_DONE 0x3 /* End of a dump */
115#define NLMSG_OVERRUN 0x4 /* Data lost */
116
117#define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
118
119struct nlmsgerr {
120 int error;
121 struct nlmsghdr msg;
122 /*
123 * followed by the message contents unless NETLINK_CAP_ACK was set
124 * or the ACK indicates success (error == 0)
125 * message length is aligned with NLMSG_ALIGN()
126 */
127 /*
128 * followed by TLVs defined in enum nlmsgerr_attrs
129 * if NETLINK_EXT_ACK was set
130 */
131};
132
133/**
134 * enum nlmsgerr_attrs - nlmsgerr attributes
135 * @NLMSGERR_ATTR_UNUSED: unused
136 * @NLMSGERR_ATTR_MSG: error message string (string)
137 * @NLMSGERR_ATTR_OFFS: offset of the invalid attribute in the original
138 * message, counting from the beginning of the header (u32)
139 * @NLMSGERR_ATTR_COOKIE: arbitrary subsystem specific cookie to
140 * be used - in the success case - to identify a created
141 * object or operation or similar (binary)
142 * @NLMSGERR_ATTR_POLICY: policy for a rejected attribute
143 * @NLMSGERR_ATTR_MISS_TYPE: type of a missing required attribute,
144 * %NLMSGERR_ATTR_MISS_NEST will not be present if the attribute was
145 * missing at the message level
146 * @NLMSGERR_ATTR_MISS_NEST: offset of the nest where attribute was missing
147 * @__NLMSGERR_ATTR_MAX: number of attributes
148 * @NLMSGERR_ATTR_MAX: highest attribute number
149 */
150enum nlmsgerr_attrs {
151 NLMSGERR_ATTR_UNUSED,
152 NLMSGERR_ATTR_MSG,
153 NLMSGERR_ATTR_OFFS,
154 NLMSGERR_ATTR_COOKIE,
155 NLMSGERR_ATTR_POLICY,
156 NLMSGERR_ATTR_MISS_TYPE,
157 NLMSGERR_ATTR_MISS_NEST,
158
159 __NLMSGERR_ATTR_MAX,
160 NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
161};
162
163#define NETLINK_ADD_MEMBERSHIP 1
164#define NETLINK_DROP_MEMBERSHIP 2
165#define NETLINK_PKTINFO 3
166#define NETLINK_BROADCAST_ERROR 4
167#define NETLINK_NO_ENOBUFS 5
168#define NETLINK_RX_RING 6
169#define NETLINK_TX_RING 7
170#define NETLINK_LISTEN_ALL_NSID 8
171#define NETLINK_LIST_MEMBERSHIPS 9
172#define NETLINK_CAP_ACK 10
173#define NETLINK_EXT_ACK 11
174#define NETLINK_GET_STRICT_CHK 12
175
176struct nl_pktinfo {
177 __u32 group;
178};
179
180struct nl_mmap_req {
181 unsigned int nm_block_size;
182 unsigned int nm_block_nr;
183 unsigned int nm_frame_size;
184 unsigned int nm_frame_nr;
185};
186
187struct nl_mmap_hdr {
188 unsigned int nm_status;
189 unsigned int nm_len;
190 __u32 nm_group;
191 /* credentials */
192 __u32 nm_pid;
193 __u32 nm_uid;
194 __u32 nm_gid;
195};
196
197enum nl_mmap_status {
198 NL_MMAP_STATUS_UNUSED,
199 NL_MMAP_STATUS_RESERVED,
200 NL_MMAP_STATUS_VALID,
201 NL_MMAP_STATUS_COPY,
202 NL_MMAP_STATUS_SKIP,
203};
204
205#define NL_MMAP_MSG_ALIGNMENT NLMSG_ALIGNTO
206#define NL_MMAP_MSG_ALIGN(sz) __ALIGN_KERNEL(sz, NL_MMAP_MSG_ALIGNMENT)
207#define NL_MMAP_HDRLEN NL_MMAP_MSG_ALIGN(sizeof(struct nl_mmap_hdr))
208
209#define NET_MAJOR 36 /* Major 36 is reserved for networking */
210
211enum {
212 NETLINK_UNCONNECTED = 0,
213 NETLINK_CONNECTED,
214};
215
216/*
217 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
218 * +---------------------+- - -+- - - - - - - - - -+- - -+
219 * | Header | Pad | Payload | Pad |
220 * | (struct nlattr) | ing | | ing |
221 * +---------------------+- - -+- - - - - - - - - -+- - -+
222 * <-------------- nlattr->nla_len -------------->
223 */
224
225struct nlattr {
226 __u16 nla_len;
227 __u16 nla_type;
228};
229
230/*
231 * nla_type (16 bits)
232 * +---+---+-------------------------------+
233 * | N | O | Attribute Type |
234 * +---+---+-------------------------------+
235 * N := Carries nested attributes
236 * O := Payload stored in network byte order
237 *
238 * Note: The N and O flag are mutually exclusive.
239 */
240#define NLA_F_NESTED (1 << 15)
241#define NLA_F_NET_BYTEORDER (1 << 14)
242#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
243
244#define NLA_ALIGNTO 4
245#define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
246#define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
247
248/* Generic 32 bitflags attribute content sent to the kernel.
249 *
250 * The value is a bitmap that defines the values being set
251 * The selector is a bitmask that defines which value is legit
252 *
253 * Examples:
254 * value = 0x0, and selector = 0x1
255 * implies we are selecting bit 1 and we want to set its value to 0.
256 *
257 * value = 0x2, and selector = 0x2
258 * implies we are selecting bit 2 and we want to set its value to 1.
259 *
260 */
261struct nla_bitfield32 {
262 __u32 value;
263 __u32 selector;
264};
265
266/*
267 * policy descriptions - it's specific to each family how this is used
268 * Normally, it should be retrieved via a dump inside another attribute
269 * specifying where it applies.
270 */
271
272/**
273 * enum netlink_attribute_type - type of an attribute
274 * @NL_ATTR_TYPE_INVALID: unused
275 * @NL_ATTR_TYPE_FLAG: flag attribute (present/not present)
276 * @NL_ATTR_TYPE_U8: 8-bit unsigned attribute
277 * @NL_ATTR_TYPE_U16: 16-bit unsigned attribute
278 * @NL_ATTR_TYPE_U32: 32-bit unsigned attribute
279 * @NL_ATTR_TYPE_U64: 64-bit unsigned attribute
280 * @NL_ATTR_TYPE_S8: 8-bit signed attribute
281 * @NL_ATTR_TYPE_S16: 16-bit signed attribute
282 * @NL_ATTR_TYPE_S32: 32-bit signed attribute
283 * @NL_ATTR_TYPE_S64: 64-bit signed attribute
284 * @NL_ATTR_TYPE_BINARY: binary data, min/max length may be specified
285 * @NL_ATTR_TYPE_STRING: string, min/max length may be specified
286 * @NL_ATTR_TYPE_NUL_STRING: NUL-terminated string,
287 * min/max length may be specified
288 * @NL_ATTR_TYPE_NESTED: nested, i.e. the content of this attribute
289 * consists of sub-attributes. The nested policy and maxtype
290 * inside may be specified.
291 * @NL_ATTR_TYPE_NESTED_ARRAY: nested array, i.e. the content of this
292 * attribute contains sub-attributes whose type is irrelevant
293 * (just used to separate the array entries) and each such array
294 * entry has attributes again, the policy for those inner ones
295 * and the corresponding maxtype may be specified.
296 * @NL_ATTR_TYPE_BITFIELD32: &struct nla_bitfield32 attribute
297 * @NL_ATTR_TYPE_SINT: 32-bit or 64-bit signed attribute, aligned to 4B
298 * @NL_ATTR_TYPE_UINT: 32-bit or 64-bit unsigned attribute, aligned to 4B
299 */
300enum netlink_attribute_type {
301 NL_ATTR_TYPE_INVALID,
302
303 NL_ATTR_TYPE_FLAG,
304
305 NL_ATTR_TYPE_U8,
306 NL_ATTR_TYPE_U16,
307 NL_ATTR_TYPE_U32,
308 NL_ATTR_TYPE_U64,
309
310 NL_ATTR_TYPE_S8,
311 NL_ATTR_TYPE_S16,
312 NL_ATTR_TYPE_S32,
313 NL_ATTR_TYPE_S64,
314
315 NL_ATTR_TYPE_BINARY,
316 NL_ATTR_TYPE_STRING,
317 NL_ATTR_TYPE_NUL_STRING,
318
319 NL_ATTR_TYPE_NESTED,
320 NL_ATTR_TYPE_NESTED_ARRAY,
321
322 NL_ATTR_TYPE_BITFIELD32,
323
324 NL_ATTR_TYPE_SINT,
325 NL_ATTR_TYPE_UINT,
326};
327
328/**
329 * enum netlink_policy_type_attr - policy type attributes
330 * @NL_POLICY_TYPE_ATTR_UNSPEC: unused
331 * @NL_POLICY_TYPE_ATTR_TYPE: type of the attribute,
332 * &enum netlink_attribute_type (U32)
333 * @NL_POLICY_TYPE_ATTR_MIN_VALUE_S: minimum value for signed
334 * integers (S64)
335 * @NL_POLICY_TYPE_ATTR_MAX_VALUE_S: maximum value for signed
336 * integers (S64)
337 * @NL_POLICY_TYPE_ATTR_MIN_VALUE_U: minimum value for unsigned
338 * integers (U64)
339 * @NL_POLICY_TYPE_ATTR_MAX_VALUE_U: maximum value for unsigned
340 * integers (U64)
341 * @NL_POLICY_TYPE_ATTR_MIN_LENGTH: minimum length for binary
342 * attributes, no minimum if not given (U32)
343 * @NL_POLICY_TYPE_ATTR_MAX_LENGTH: maximum length for binary
344 * attributes, no maximum if not given (U32)
345 * @NL_POLICY_TYPE_ATTR_POLICY_IDX: sub policy for nested and
346 * nested array types (U32)
347 * @NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE: maximum sub policy
348 * attribute for nested and nested array types, this can
349 * in theory be < the size of the policy pointed to by
350 * the index, if limited inside the nesting (U32)
351 * @NL_POLICY_TYPE_ATTR_BITFIELD32_MASK: valid mask for the
352 * bitfield32 type (U32)
353 * @NL_POLICY_TYPE_ATTR_MASK: mask of valid bits for unsigned integers (U64)
354 * @NL_POLICY_TYPE_ATTR_PAD: pad attribute for 64-bit alignment
355 *
356 * @__NL_POLICY_TYPE_ATTR_MAX: number of attributes
357 * @NL_POLICY_TYPE_ATTR_MAX: highest attribute number
358 */
359enum netlink_policy_type_attr {
360 NL_POLICY_TYPE_ATTR_UNSPEC,
361 NL_POLICY_TYPE_ATTR_TYPE,
362 NL_POLICY_TYPE_ATTR_MIN_VALUE_S,
363 NL_POLICY_TYPE_ATTR_MAX_VALUE_S,
364 NL_POLICY_TYPE_ATTR_MIN_VALUE_U,
365 NL_POLICY_TYPE_ATTR_MAX_VALUE_U,
366 NL_POLICY_TYPE_ATTR_MIN_LENGTH,
367 NL_POLICY_TYPE_ATTR_MAX_LENGTH,
368 NL_POLICY_TYPE_ATTR_POLICY_IDX,
369 NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE,
370 NL_POLICY_TYPE_ATTR_BITFIELD32_MASK,
371 NL_POLICY_TYPE_ATTR_PAD,
372 NL_POLICY_TYPE_ATTR_MASK,
373
374 /* keep last */
375 __NL_POLICY_TYPE_ATTR_MAX,
376 NL_POLICY_TYPE_ATTR_MAX = __NL_POLICY_TYPE_ATTR_MAX - 1
377};
378
379#endif /* __LINUX_NETLINK_H */