netlink.h

  1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2#ifndef _UAPI__LINUX_NETLINK_H
  3#define _UAPI__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#ifndef __KERNEL__
151#define NETLINK_RX_RING			6
152#define NETLINK_TX_RING			7
153#endif
154#define NETLINK_LISTEN_ALL_NSID		8
155#define NETLINK_LIST_MEMBERSHIPS	9
156#define NETLINK_CAP_ACK			10
157#define NETLINK_EXT_ACK			11
158#define NETLINK_GET_STRICT_CHK		12
159
160struct nl_pktinfo {
161	__u32	group;
162};
163
164struct nl_mmap_req {
165	unsigned int	nm_block_size;
166	unsigned int	nm_block_nr;
167	unsigned int	nm_frame_size;
168	unsigned int	nm_frame_nr;
169};
170
171struct nl_mmap_hdr {
172	unsigned int	nm_status;
173	unsigned int	nm_len;
174	__u32		nm_group;
175	/* credentials */
176	__u32		nm_pid;
177	__u32		nm_uid;
178	__u32		nm_gid;
179};
180
181#ifndef __KERNEL__
182enum nl_mmap_status {
183	NL_MMAP_STATUS_UNUSED,
184	NL_MMAP_STATUS_RESERVED,
185	NL_MMAP_STATUS_VALID,
186	NL_MMAP_STATUS_COPY,
187	NL_MMAP_STATUS_SKIP,
188};
189
190#define NL_MMAP_MSG_ALIGNMENT		NLMSG_ALIGNTO
191#define NL_MMAP_MSG_ALIGN(sz)		__ALIGN_KERNEL(sz, NL_MMAP_MSG_ALIGNMENT)
192#define NL_MMAP_HDRLEN			NL_MMAP_MSG_ALIGN(sizeof(struct nl_mmap_hdr))
193#endif
194
195#define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/
196
197enum {
198	NETLINK_UNCONNECTED = 0,
199	NETLINK_CONNECTED,
200};
201
202/*
203 *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
204 * +---------------------+- - -+- - - - - - - - - -+- - -+
205 * |        Header       | Pad |     Payload       | Pad |
206 * |   (struct nlattr)   | ing |                   | ing |
207 * +---------------------+- - -+- - - - - - - - - -+- - -+
208 *  <-------------- nlattr->nla_len -------------->
209 */
210
211struct nlattr {
212	__u16           nla_len;
213	__u16           nla_type;
214};
215
216/*
217 * nla_type (16 bits)
218 * +---+---+-------------------------------+
219 * | N | O | Attribute Type                |
220 * +---+---+-------------------------------+
221 * N := Carries nested attributes
222 * O := Payload stored in network byte order
223 *
224 * Note: The N and O flag are mutually exclusive.
225 */
226#define NLA_F_NESTED		(1 << 15)
227#define NLA_F_NET_BYTEORDER	(1 << 14)
228#define NLA_TYPE_MASK		~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
229
230#define NLA_ALIGNTO		4
231#define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
232#define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))
233
234/* Generic 32 bitflags attribute content sent to the kernel.
235 *
236 * The value is a bitmap that defines the values being set
237 * The selector is a bitmask that defines which value is legit
238 *
239 * Examples:
240 *  value = 0x0, and selector = 0x1
241 *  implies we are selecting bit 1 and we want to set its value to 0.
242 *
243 *  value = 0x2, and selector = 0x2
244 *  implies we are selecting bit 2 and we want to set its value to 1.
245 *
246 */
247struct nla_bitfield32 {
248	__u32 value;
249	__u32 selector;
250};
251
252#endif /* _UAPI__LINUX_NETLINK_H */