1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27#ifndef	_NETLINK_NETLINK_SNL_GENERIC_H_
28#define	_NETLINK_NETLINK_SNL_GENERIC_H_
29
30#include <netlink/netlink.h>
31#include <netlink/netlink_generic.h>
32#include <netlink/netlink_snl.h>
33
34/* Genetlink helpers */
35static inline struct nlmsghdr *
36snl_create_genl_msg_request(struct snl_writer *nw, int genl_family, uint8_t genl_cmd)
37{
38	assert(nw->hdr == NULL);
39
40	struct nlmsghdr *hdr = snl_reserve_msg_object(nw, struct nlmsghdr);
41	hdr->nlmsg_type = genl_family;
42	hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
43	nw->hdr = hdr;
44	struct genlmsghdr *ghdr = snl_reserve_msg_object(nw, struct genlmsghdr);
45	ghdr->cmd = genl_cmd;
46
47	return (hdr);
48}
49
50static struct snl_field_parser snl_fp_genl[] = {};
51
52#define	SNL_DECLARE_GENL_PARSER(_name, _np)	SNL_DECLARE_PARSER(_name,\
53    struct genlmsghdr, snl_fp_genl, _np)
54
55struct snl_genl_ctrl_mcast_group {
56	uint32_t mcast_grp_id;
57	char *mcast_grp_name;
58};
59
60struct snl_genl_ctrl_mcast_groups {
61	uint32_t num_groups;
62	struct snl_genl_ctrl_mcast_group **groups;
63};
64
65#define	_OUT(_field)	offsetof(struct snl_genl_ctrl_mcast_group, _field)
66static struct snl_attr_parser _nla_p_getmc[] = {
67	{ .type = CTRL_ATTR_MCAST_GRP_NAME, .off = _OUT(mcast_grp_name), .cb = snl_attr_get_string },
68	{ .type = CTRL_ATTR_MCAST_GRP_ID, .off = _OUT(mcast_grp_id), .cb = snl_attr_get_uint32 },
69};
70#undef _OUT
71SNL_DECLARE_ATTR_PARSER_EXT(_genl_ctrl_mc_parser,
72		sizeof(struct snl_genl_ctrl_mcast_group),
73		_nla_p_getmc, NULL);
74
75struct _getfamily_attrs {
76	uint16_t family_id;
77	char	*family_name;
78	struct snl_genl_ctrl_mcast_groups mcast_groups;
79};
80
81#define	_IN(_field)	offsetof(struct genlmsghdr, _field)
82#define	_OUT(_field)	offsetof(struct _getfamily_attrs, _field)
83static struct snl_attr_parser _nla_p_getfam[] = {
84	{ .type = CTRL_ATTR_FAMILY_ID , .off = _OUT(family_id), .cb = snl_attr_get_uint16 },
85	{ .type = CTRL_ATTR_FAMILY_NAME, .off = _OUT(family_name), .cb = snl_attr_get_string },
86	{
87		.type = CTRL_ATTR_MCAST_GROUPS,
88		.off = _OUT(mcast_groups),
89		.cb = snl_attr_get_parray,
90		.arg = &_genl_ctrl_mc_parser,
91	},
92};
93#undef _IN
94#undef _OUT
95SNL_DECLARE_GENL_PARSER(_genl_ctrl_getfam_parser, _nla_p_getfam);
96
97static bool
98snl_get_genl_family_info(struct snl_state *ss, const char *family_name,
99    struct _getfamily_attrs *attrs)
100{
101	struct snl_writer nw;
102	struct nlmsghdr *hdr;
103
104	memset(attrs, 0, sizeof(*attrs));
105
106	snl_init_writer(ss, &nw);
107	hdr = snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY);
108	snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, family_name);
109	if ((hdr = snl_finalize_msg(&nw)) == NULL || !snl_send_message(ss, hdr))
110		return (false);
111
112	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
113	if (hdr != NULL && hdr->nlmsg_type != NLMSG_ERROR) {
114		if (snl_parse_nlmsg(ss, hdr, &_genl_ctrl_getfam_parser, attrs))
115			return (true);
116	}
117
118	return (false);
119}
120
121static inline uint16_t
122snl_get_genl_family(struct snl_state *ss, const char *family_name)
123{
124	struct _getfamily_attrs attrs = {};
125
126	snl_get_genl_family_info(ss, family_name, &attrs);
127	return (attrs.family_id);
128}
129
130static const struct snl_hdr_parser *snl_all_genl_parsers[] = {
131	&_genl_ctrl_getfam_parser, &_genl_ctrl_mc_parser,
132};
133
134#endif
135