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/kernel.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 */
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
44struct nlmsghdr {
45 __u32 nlmsg_len; /* Length of message including header */
46 __u16 nlmsg_type; /* Message content */
47 __u16 nlmsg_flags; /* Additional flags */
48 __u32 nlmsg_seq; /* Sequence number */
49 __u32 nlmsg_pid; /* Sending process port ID */
50};
51
52/* Flags values */
53
54#define NLM_F_REQUEST 0x01 /* It is request message. */
55#define NLM_F_MULTI 0x02 /* Multipart message, terminated by NLMSG_DONE */
56#define NLM_F_ACK 0x04 /* Reply with ack, with zero or error code */
57#define NLM_F_ECHO 0x08 /* Echo this request */
58#define NLM_F_DUMP_INTR 0x10 /* Dump was inconsistent due to sequence change */
59#define NLM_F_DUMP_FILTERED 0x20 /* Dump was filtered as requested */
60
61/* Modifiers to GET request */
62#define NLM_F_ROOT 0x100 /* specify tree root */
63#define NLM_F_MATCH 0x200 /* return all matching */
64#define NLM_F_ATOMIC 0x400 /* atomic GET */
65#define NLM_F_DUMP (NLM_F_ROOT|NLM_F_MATCH)
66
67/* Modifiers to NEW request */
68#define NLM_F_REPLACE 0x100 /* Override existing */
69#define NLM_F_EXCL 0x200 /* Do not touch, if it exists */
70#define NLM_F_CREATE 0x400 /* Create, if it does not exist */
71#define NLM_F_APPEND 0x800 /* Add to end of list */
72
73/* Modifiers to DELETE request */
74#define NLM_F_NONREC 0x100 /* Do not delete recursively */
75
76/* Flags for ACK message */
77#define NLM_F_CAPPED 0x100 /* request was capped */
78#define NLM_F_ACK_TLVS 0x200 /* extended ACK TVLs were included */
79
80/*
81 4.4BSD ADD NLM_F_CREATE|NLM_F_EXCL
82 4.4BSD CHANGE NLM_F_REPLACE
83
84 True CHANGE NLM_F_CREATE|NLM_F_REPLACE
85 Append NLM_F_CREATE
86 Check NLM_F_EXCL
87 */
88
89#define NLMSG_ALIGNTO 4U
90#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
91#define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
92#define NLMSG_LENGTH(len) ((len) + NLMSG_HDRLEN)
93#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
94#define NLMSG_DATA(nlh) ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
95#define NLMSG_NEXT(nlh,len) ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
96 (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
97#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
98 (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
99 (nlh)->nlmsg_len <= (len))
100#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
101
102#define NLMSG_NOOP 0x1 /* Nothing. */
103#define NLMSG_ERROR 0x2 /* Error */
104#define NLMSG_DONE 0x3 /* End of a dump */
105#define NLMSG_OVERRUN 0x4 /* Data lost */
106
107#define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
108
109struct nlmsgerr {
110 int error;
111 struct nlmsghdr msg;
112 /*
113 * followed by the message contents unless NETLINK_CAP_ACK was set
114 * or the ACK indicates success (error == 0)
115 * message length is aligned with NLMSG_ALIGN()
116 */
117 /*
118 * followed by TLVs defined in enum nlmsgerr_attrs
119 * if NETLINK_EXT_ACK was set
120 */
121};
122
123/**
124 * enum nlmsgerr_attrs - nlmsgerr attributes
125 * @NLMSGERR_ATTR_UNUSED: unused
126 * @NLMSGERR_ATTR_MSG: error message string (string)
127 * @NLMSGERR_ATTR_OFFS: offset of the invalid attribute in the original
128 * message, counting from the beginning of the header (u32)
129 * @NLMSGERR_ATTR_COOKIE: arbitrary subsystem specific cookie to
130 * be used - in the success case - to identify a created
131 * object or operation or similar (binary)
132 * @__NLMSGERR_ATTR_MAX: number of attributes
133 * @NLMSGERR_ATTR_MAX: highest attribute number
134 */
135enum nlmsgerr_attrs {
136 NLMSGERR_ATTR_UNUSED,
137 NLMSGERR_ATTR_MSG,
138 NLMSGERR_ATTR_OFFS,
139 NLMSGERR_ATTR_COOKIE,
140
141 __NLMSGERR_ATTR_MAX,
142 NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
143};
144
145#define NETLINK_ADD_MEMBERSHIP 1
146#define NETLINK_DROP_MEMBERSHIP 2
147#define NETLINK_PKTINFO 3
148#define NETLINK_BROADCAST_ERROR 4
149#define NETLINK_NO_ENOBUFS 5
150#define NETLINK_RX_RING 6
151#define NETLINK_TX_RING 7
152#define NETLINK_LISTEN_ALL_NSID 8
153#define NETLINK_LIST_MEMBERSHIPS 9
154#define NETLINK_CAP_ACK 10
155#define NETLINK_EXT_ACK 11
156#define NETLINK_GET_STRICT_CHK 12
157
158struct nl_pktinfo {
159 __u32 group;
160};
161
162struct nl_mmap_req {
163 unsigned int nm_block_size;
164 unsigned int nm_block_nr;
165 unsigned int nm_frame_size;
166 unsigned int nm_frame_nr;
167};
168
169struct nl_mmap_hdr {
170 unsigned int nm_status;
171 unsigned int nm_len;
172 __u32 nm_group;
173 /* credentials */
174 __u32 nm_pid;
175 __u32 nm_uid;
176 __u32 nm_gid;
177};
178
179enum nl_mmap_status {
180 NL_MMAP_STATUS_UNUSED,
181 NL_MMAP_STATUS_RESERVED,
182 NL_MMAP_STATUS_VALID,
183 NL_MMAP_STATUS_COPY,
184 NL_MMAP_STATUS_SKIP,
185};
186
187#define NL_MMAP_MSG_ALIGNMENT NLMSG_ALIGNTO
188#define NL_MMAP_MSG_ALIGN(sz) __ALIGN_KERNEL(sz, NL_MMAP_MSG_ALIGNMENT)
189#define NL_MMAP_HDRLEN NL_MMAP_MSG_ALIGN(sizeof(struct nl_mmap_hdr))
190
191#define NET_MAJOR 36 /* Major 36 is reserved for networking */
192
193enum {
194 NETLINK_UNCONNECTED = 0,
195 NETLINK_CONNECTED,
196};
197
198/*
199 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
200 * +---------------------+- - -+- - - - - - - - - -+- - -+
201 * | Header | Pad | Payload | Pad |
202 * | (struct nlattr) | ing | | ing |
203 * +---------------------+- - -+- - - - - - - - - -+- - -+
204 * <-------------- nlattr->nla_len -------------->
205 */
206
207struct nlattr {
208 __u16 nla_len;
209 __u16 nla_type;
210};
211
212/*
213 * nla_type (16 bits)
214 * +---+---+-------------------------------+
215 * | N | O | Attribute Type |
216 * +---+---+-------------------------------+
217 * N := Carries nested attributes
218 * O := Payload stored in network byte order
219 *
220 * Note: The N and O flag are mutually exclusive.
221 */
222#define NLA_F_NESTED (1 << 15)
223#define NLA_F_NET_BYTEORDER (1 << 14)
224#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
225
226#define NLA_ALIGNTO 4
227#define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
228#define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
229
230/* Generic 32 bitflags attribute content sent to the kernel.
231 *
232 * The value is a bitmap that defines the values being set
233 * The selector is a bitmask that defines which value is legit
234 *
235 * Examples:
236 * value = 0x0, and selector = 0x1
237 * implies we are selecting bit 1 and we want to set its value to 0.
238 *
239 * value = 0x2, and selector = 0x2
240 * implies we are selecting bit 2 and we want to set its value to 1.
241 *
242 */
243struct nla_bitfield32 {
244 __u32 value;
245 __u32 selector;
246};
247
248#endif /* __LINUX_NETLINK_H */
249