1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2021 Ng Peng Nam Sean
5 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * Copyright (C) The Internet Society (2003). All Rights Reserved.
29 *
30 * This document and translations of it may be copied and furnished to
31 * others, and derivative works that comment on or otherwise explain it
32 * or assist in its implementation may be prepared, copied, published
33 * and distributed, in whole or in part, without restriction of any
34 * kind, provided that the above copyright notice and this paragraph are
35 * included on all such copies and derivative works. However, this
36 * document itself may not be modified in any way, such as by removing
37 * the copyright notice or references to the Internet Society or other
38 * Internet organizations, except as needed for the purpose of
39 * developing Internet standards in which case the procedures for
40 * copyrights defined in the Internet Standards process must be
41 * followed, or as required to translate it into languages other than
42 * English.
43 *
44 * The limited permissions granted above are perpetual and will not be
45 * revoked by the Internet Society or its successors or assignees.
46 *
47 * This document and the information contained herein is provided on an
48 * "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
49 * TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
50 * BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
51 * HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
52 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
53
54 */
55
56/*
57 * This file contains structures and constants for RFC 3549 (Netlink)
58 * protocol. Some values have been taken from Linux implementation.
59 */
60
61#ifndef _NETLINK_NETLINK_H_
62#define _NETLINK_NETLINK_H_
63
64#include <sys/param.h>
65#include <sys/socket.h>
66
67struct sockaddr_nl {
68 uint8_t nl_len; /* sizeof(sockaddr_nl) */
69 sa_family_t nl_family; /* netlink family */
70 uint16_t nl_pad; /* reserved, set to 0 */
71 uint32_t nl_pid; /* desired port ID, 0 for auto-select */
72 uint32_t nl_groups; /* multicast groups mask to bind to */
73};
74
75#define SOL_NETLINK 270
76
77/* Netlink socket options */
78#define NETLINK_ADD_MEMBERSHIP 1 /* Subscribe for the specified group notifications */
79#define NETLINK_DROP_MEMBERSHIP 2 /* Unsubscribe from the specified group */
80#define NETLINK_PKTINFO 3 /* XXX: not supported */
81#define NETLINK_BROADCAST_ERROR 4 /* XXX: not supported */
82#define NETLINK_NO_ENOBUFS 5 /* XXX: not supported */
83#define NETLINK_RX_RING 6 /* XXX: not supported */
84#define NETLINK_TX_RING 7 /* XXX: not supported */
85#define NETLINK_LISTEN_ALL_NSID 8 /* XXX: not supported */
86
87#define NETLINK_LIST_MEMBERSHIPS 9
88#define NETLINK_CAP_ACK 10 /* Send only original message header in the reply */
89#define NETLINK_EXT_ACK 11 /* Ack support for receiving additional TLVs in ack */
90#define NETLINK_GET_STRICT_CHK 12 /* Strict header checking */
91
92#define NETLINK_MSG_INFO 257 /* (FreeBSD-specific) Receive message originator data in cmsg */
93
94/*
95 * RFC 3549, 2.3.2 Netlink Message Header
96 */
97struct nlmsghdr {
98 uint32_t nlmsg_len; /* Length of message including header */
99 uint16_t nlmsg_type; /* Message type identifier */
100 uint16_t nlmsg_flags; /* Flags (NLM_F_) */
101 uint32_t nlmsg_seq; /* Sequence number */
102 uint32_t nlmsg_pid; /* Sending process port ID */
103};
104
105/*
106 * RFC 3549, 2.3.2 standard flag bits (nlmsg_flags)
107 */
108#define NLM_F_REQUEST 0x01 /* Indicateds request to kernel */
109#define NLM_F_MULTI 0x02 /* Message is part of a group terminated by NLMSG_DONE msg */
110#define NLM_F_ACK 0x04 /* Reply with ack message containing resulting error code */
111#define NLM_F_ECHO 0x08 /* (not supported) Echo this request back */
112#define NLM_F_DUMP_INTR 0x10 /* Dump was inconsistent due to sequence change */
113#define NLM_F_DUMP_FILTERED 0x20 /* Dump was filtered as requested */
114
115/*
116 * RFC 3549, 2.3.2 Additional flag bits for GET requests
117 */
118#define NLM_F_ROOT 0x100 /* Return the complete table */
119#define NLM_F_MATCH 0x200 /* Return all entries matching criteria */
120#define NLM_F_ATOMIC 0x400 /* Return an atomic snapshot (ignored) */
121#define NLM_F_DUMP (NLM_F_ROOT | NLM_F_MATCH)
122
123/*
124 * RFC 3549, 2.3.2 Additional flag bits for NEW requests
125 */
126#define NLM_F_REPLACE 0x100 /* Replace existing matching config object */
127#define NLM_F_EXCL 0x200 /* Don't replace the object if exists */
128#define NLM_F_CREATE 0x400 /* Create if it does not exist */
129#define NLM_F_APPEND 0x800 /* Add to end of list */
130
131/* Modifiers to DELETE requests */
132#define NLM_F_NONREC 0x100 /* Do not delete recursively */
133
134/* Flags for ACK message */
135#define NLM_F_CAPPED 0x100 /* request was capped */
136#define NLM_F_ACK_TLVS 0x200 /* extended ACK TVLs were included */
137
138/*
139 * RFC 3549, 2.3.2 standard message types (nlmsg_type).
140 */
141#define NLMSG_NOOP 0x1 /* Message is ignored. */
142#define NLMSG_ERROR 0x2 /* reply error code reporting */
143#define NLMSG_DONE 0x3 /* Message terminates a multipart message. */
144#define NLMSG_OVERRUN 0x4 /* overrun detected, data is lost */
145
146#define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
147
148/*
149 * Defition of numbers assigned to the netlink subsystems.
150 */
151#define NETLINK_ROUTE 0 /* Routing/device hook */
152#define NETLINK_UNUSED 1 /* not supported */
153#define NETLINK_USERSOCK 2 /* not supported */
154#define NETLINK_FIREWALL 3 /* not supported */
155#define NETLINK_SOCK_DIAG 4 /* not supported */
156#define NETLINK_NFLOG 5 /* not supported */
157#define NETLINK_XFRM 6 /* (not supported) PF_SETKEY */
158#define NETLINK_SELINUX 7 /* not supported */
159#define NETLINK_ISCSI 8 /* not supported */
160#define NETLINK_AUDIT 9 /* not supported */
161#define NETLINK_FIB_LOOKUP 10 /* not supported */
162#define NETLINK_CONNECTOR 11 /* not supported */
163#define NETLINK_NETFILTER 12 /* not supported */
164#define NETLINK_IP6_FW 13 /* not supported */
165#define NETLINK_DNRTMSG 14 /* not supported */
166#define NETLINK_KOBJECT_UEVENT 15 /* not supported */
167#define NETLINK_GENERIC 16 /* Generic netlink (dynamic families) */
168
169/*
170 * RFC 3549, 2.3.2.2 The ACK Netlink Message
171 */
172struct nlmsgerr {
173 int error;
174 struct nlmsghdr msg;
175};
176
177enum nlmsgerr_attrs {
178 NLMSGERR_ATTR_UNUSED,
179 NLMSGERR_ATTR_MSG = 1, /* string, error message */
180 NLMSGERR_ATTR_OFFS = 2, /* u32, offset of the invalid attr from nl header */
181 NLMSGERR_ATTR_COOKIE = 3, /* binary, data to pass to userland */
182 NLMSGERR_ATTR_POLICY = 4, /* not supported */
183 __NLMSGERR_ATTR_MAX,
184 NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
185};
186
187/* FreeBSD-specific debugging info */
188
189enum nlmsginfo_attrs {
190 NLMSGINFO_ATTR_UNUSED,
191 NLMSGINFO_ATTR_PROCESS_ID = 1, /* u32, source process PID */
192 NLMSGINFO_ATTR_PORT_ID = 2, /* u32, source socket nl_pid */
193 NLMSGINFO_ATTR_SEQ_ID = 3, /* u32, source message seq_id */
194};
195
196
197#define NL_ITEM_ALIGN_SIZE sizeof(uint32_t)
198#define NL_ITEM_ALIGN(_len) __align_up(_len, NL_ITEM_ALIGN_SIZE)
199#define NL_ITEM_DATA(_ptr, _off) ((void *)((char *)(_ptr) + _off))
200#define NL_ITEM_DATA_CONST(_ptr, _off) ((const void *)((const char *)(_ptr) + _off))
201
202#define NL_ITEM_OK(_ptr, _len, _hlen, _LEN_M) \
203 ((_len) >= _hlen && _LEN_M(_ptr) >= _hlen && _LEN_M(_ptr) <= (_len))
204#define NL_ITEM_NEXT(_ptr, _LEN_M) ((__typeof(_ptr))((char *)(_ptr) + _LEN_M(_ptr)))
205#define NL_ITEM_ITER(_ptr, _len, _LEN_MACRO) \
206 ((_len) -= _LEN_MACRO(_ptr), NL_ITEM_NEXT(_ptr, _LEN_MACRO))
207
208/* part of netlink(3) API */
209#define NLMSG_ALIGNTO NL_ITEM_ALIGN_SIZE
210#define NLMSG_ALIGN(_len) NL_ITEM_ALIGN(_len)
211
212#ifndef _KERNEL
213/* part of netlink(3) API */
214#define NLMSG_HDRLEN (sizeof(struct nlmsghdr))
215#define NLMSG_LENGTH(_len) ((_len) + NLMSG_HDRLEN)
216#define NLMSG_SPACE(_len) NLMSG_ALIGN(NLMSG_LENGTH(_len))
217#define NLMSG_DATA(_hdr) NL_ITEM_DATA(_hdr, NLMSG_HDRLEN)
218#define _NLMSG_LEN(_hdr) ((_hdr)->nlmsg_len)
219#define _NLMSG_ALIGNED_LEN(_hdr) NLMSG_ALIGN(_NLMSG_LEN(_hdr))
220#define NLMSG_OK(_hdr, _len) NL_ITEM_OK(_hdr, _len, NLMSG_HDRLEN, _NLMSG_LEN)
221#define NLMSG_PAYLOAD(_hdr,_len) (_NLMSG_LEN(_hdr) - NLMSG_SPACE((_len)))
222#define NLMSG_NEXT(_hdr, _len) NL_ITEM_ITER(_hdr, _len, _NLMSG_ALIGNED_LEN)
223
224#else
225#define NLMSG_HDRLEN (NLMSG_ALIGN(sizeof(struct nlmsghdr)))
226#endif
227
228/*
229 * Base netlink attribute TLV header.
230 */
231struct nlattr {
232 uint16_t nla_len; /* Total attribute length */
233 uint16_t nla_type; /* Attribute type */
234};
235
236/*
237 *
238 * nl_type field enconding:
239 *
240 * 0 1
241 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6
242 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
243 * |N|O| Attribute type |
244 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
245 * N - attribute contains other attributes (mostly unused)
246 * O - encoded in network byte order (mostly unused)
247 * Note: N & O are mutually exclusive
248 *
249 * Note: attribute type value scope normally is either parent attribute
250 * or the message/message group.
251 */
252
253#define NLA_F_NESTED (1 << 15)
254#define NLA_F_NET_BYTEORDER (1 << 14)
255#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
256
257#ifndef _KERNEL
258#define NLA_ALIGNTO NL_ITEM_ALIGN_SIZE
259#define NLA_ALIGN(_len) NL_ITEM_ALIGN(_len)
260#define NLA_HDRLEN ((int)sizeof(struct nlattr))
261#endif
262
263#endif