2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2021 Ng Peng Nam Sean
5 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
29 #ifndef _NETLINK_NETLINK_MESSAGE_WRITER_H_
30 #define _NETLINK_NETLINK_MESSAGE_WRITER_H_
34 #include <netinet/in.h>
37 * It is not meant to be included directly
42 typedef bool nl_writer_cb(struct nl_writer *nw);
45 struct nl_buf *buf; /* Underlying storage pointer */
46 struct nlmsghdr *hdr; /* Pointer to the currently-filled msg */
47 nl_writer_cb *cb; /* Callback to flush data */
55 u_int num_messages; /* Number of messages in the buffer */
56 int malloc_flag; /* M_WAITOK or M_NOWAIT */
57 bool ignore_limit; /* If true, ignores RCVBUF limit */
58 bool enomem; /* True if ENOMEM occured */
59 bool suppress_ack; /* If true, don't send NLMSG_ERR */
62 #define NLMSG_SMALL 128
63 #define NLMSG_LARGE 2048
65 /* Message and attribute writing */
66 #if defined(NETLINK) || defined(NETLINK_MODULE)
67 /* Provide optimized calls to the functions inside the same linking unit */
69 bool _nlmsg_get_unicast_writer(struct nl_writer *nw, int expected_size, struct nlpcb *nlp);
70 bool _nlmsg_get_group_writer(struct nl_writer *nw, int expected_size, int proto, int group_id);
71 bool _nlmsg_flush(struct nl_writer *nw);
72 void _nlmsg_ignore_limit(struct nl_writer *nw);
74 bool _nlmsg_refill_buffer(struct nl_writer *nw, u_int required_len);
75 bool _nlmsg_add(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type,
76 uint16_t flags, uint32_t len);
77 bool _nlmsg_end(struct nl_writer *nw);
78 void _nlmsg_abort(struct nl_writer *nw);
80 bool _nlmsg_end_dump(struct nl_writer *nw, int error, struct nlmsghdr *hdr);
84 nlmsg_get_unicast_writer(struct nl_writer *nw, int expected_size, struct nlpcb *nlp)
86 return (_nlmsg_get_unicast_writer(nw, expected_size, nlp));
90 nlmsg_get_group_writer(struct nl_writer *nw, int expected_size, int proto, int group_id)
92 return (_nlmsg_get_group_writer(nw, expected_size, proto, group_id));
96 nlmsg_flush(struct nl_writer *nw)
98 return (_nlmsg_flush(nw));
102 nlmsg_ignore_limit(struct nl_writer *nw)
104 _nlmsg_ignore_limit(nw);
108 nlmsg_refill_buffer(struct nl_writer *nw, int required_size)
110 return (_nlmsg_refill_buffer(nw, required_size));
114 nlmsg_add(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type,
115 uint16_t flags, uint32_t len)
117 return (_nlmsg_add(nw, portid, seq, type, flags, len));
121 nlmsg_end(struct nl_writer *nw)
123 return (_nlmsg_end(nw));
127 nlmsg_abort(struct nl_writer *nw)
129 return (_nlmsg_abort(nw));
133 nlmsg_end_dump(struct nl_writer *nw, int error, struct nlmsghdr *hdr)
135 return (_nlmsg_end_dump(nw, error, hdr));
139 /* Provide access to the functions via netlink_glue.c */
141 bool nlmsg_get_unicast_writer(struct nl_writer *nw, int expected_size, struct nlpcb *nlp);
142 bool nlmsg_get_group_writer(struct nl_writer *nw, int expected_size, int proto, int group_id);
143 bool nlmsg_get_chain_writer(struct nl_writer *nw, int expected_size, struct mbuf **pm);
144 bool nlmsg_flush(struct nl_writer *nw);
145 void nlmsg_ignore_limit(struct nl_writer *nw);
147 bool nlmsg_refill_buffer(struct nl_writer *nw, int required_size);
148 bool nlmsg_add(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type,
149 uint16_t flags, uint32_t len);
150 bool nlmsg_end(struct nl_writer *nw);
151 void nlmsg_abort(struct nl_writer *nw);
153 bool nlmsg_end_dump(struct nl_writer *nw, int error, struct nlmsghdr *hdr);
155 #endif /* defined(NETLINK) || defined(NETLINK_MODULE) */
158 nlmsg_reply(struct nl_writer *nw, const struct nlmsghdr *hdr, int payload_len)
160 return (nlmsg_add(nw, hdr->nlmsg_pid, hdr->nlmsg_seq, hdr->nlmsg_type,
161 hdr->nlmsg_flags, payload_len));
165 * KPI similar to mtodo():
166 * current (uncompleted) header is guaranteed to be contiguous,
167 * but can be reallocated, thus pointers may need to be readjusted.
169 u_int nlattr_save_offset(const struct nl_writer *nw);
172 _nlattr_restore_offset(const struct nl_writer *nw, int off)
174 return ((void *)((char *)nw->hdr + off));
176 #define nlattr_restore_offset(_ns, _off, _t) ((_t *)_nlattr_restore_offset(_ns, _off))
179 nlattr_set_len(const struct nl_writer *nw, int off)
181 struct nlattr *nla = nlattr_restore_offset(nw, off, struct nlattr);
182 nla->nla_len = nlattr_save_offset(nw) - off;
185 void *nlmsg_reserve_data_raw(struct nl_writer *nw, size_t sz);
186 #define nlmsg_reserve_object(_ns, _t) ((_t *)nlmsg_reserve_data_raw(_ns, sizeof(_t)))
187 #define nlmsg_reserve_data(_ns, _sz, _t) ((_t *)nlmsg_reserve_data_raw(_ns, _sz))
190 nlattr_add_nested(struct nl_writer *nw, uint16_t nla_type)
192 int off = nlattr_save_offset(nw);
193 struct nlattr *nla = nlmsg_reserve_data(nw, sizeof(struct nlattr), struct nlattr);
194 if (__predict_false(nla == NULL))
196 nla->nla_type = nla_type;
201 _nlmsg_reserve_attr(struct nl_writer *nw, uint16_t nla_type, uint16_t sz)
203 sz += sizeof(struct nlattr);
205 struct nlattr *nla = nlmsg_reserve_data(nw, sz, struct nlattr);
206 if (__predict_false(nla == NULL))
208 nla->nla_type = nla_type;
211 return ((void *)(nla + 1));
213 #define nlmsg_reserve_attr(_ns, _at, _t) ((_t *)_nlmsg_reserve_attr(_ns, _at, NLA_ALIGN(sizeof(_t))))
215 bool nlattr_add(struct nl_writer *nw, int attr_type, int attr_len,
219 nlattr_add_raw(struct nl_writer *nw, const struct nlattr *nla_src)
221 int attr_len = nla_src->nla_len - sizeof(struct nlattr);
223 MPASS(attr_len >= 0);
225 return (nlattr_add(nw, nla_src->nla_type, attr_len, (const void *)(nla_src + 1)));
229 nlattr_add_bool(struct nl_writer *nw, int attrtype, bool value)
231 return (nlattr_add(nw, attrtype, sizeof(bool), &value));
235 nlattr_add_u8(struct nl_writer *nw, int attrtype, uint8_t value)
237 return (nlattr_add(nw, attrtype, sizeof(uint8_t), &value));
241 nlattr_add_u16(struct nl_writer *nw, int attrtype, uint16_t value)
243 return (nlattr_add(nw, attrtype, sizeof(uint16_t), &value));
247 nlattr_add_u32(struct nl_writer *nw, int attrtype, uint32_t value)
249 return (nlattr_add(nw, attrtype, sizeof(uint32_t), &value));
253 nlattr_add_u64(struct nl_writer *nw, int attrtype, uint64_t value)
255 return (nlattr_add(nw, attrtype, sizeof(uint64_t), &value));
259 nlattr_add_s8(struct nl_writer *nw, int attrtype, int8_t value)
261 return (nlattr_add(nw, attrtype, sizeof(int8_t), &value));
265 nlattr_add_s16(struct nl_writer *nw, int attrtype, int16_t value)
267 return (nlattr_add(nw, attrtype, sizeof(int16_t), &value));
271 nlattr_add_s32(struct nl_writer *nw, int attrtype, int32_t value)
273 return (nlattr_add(nw, attrtype, sizeof(int32_t), &value));
277 nlattr_add_s64(struct nl_writer *nw, int attrtype, int64_t value)
279 return (nlattr_add(nw, attrtype, sizeof(int64_t), &value));
283 nlattr_add_flag(struct nl_writer *nw, int attrtype)
285 return (nlattr_add(nw, attrtype, 0, NULL));
289 nlattr_add_string(struct nl_writer *nw, int attrtype, const char *str)
291 return (nlattr_add(nw, attrtype, strlen(str) + 1, str));
295 nlattr_add_in_addr(struct nl_writer *nw, int attrtype, const struct in_addr *in)
297 return (nlattr_add(nw, attrtype, sizeof(*in), in));
301 nlattr_add_in6_addr(struct nl_writer *nw, int attrtype, const struct in6_addr *in6)
303 return (nlattr_add(nw, attrtype, sizeof(*in6), in6));