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, uint16_t genl_family,
37 uint8_t genl_cmd)
38{
39 struct nlmsghdr *hdr;
40 struct genlmsghdr *ghdr;
41
42 assert(nw->hdr == NULL);
43
44 hdr = snl_reserve_msg_object(nw, struct nlmsghdr);
45 if (__predict_false(hdr == NULL))
46 return (NULL);
47 hdr->nlmsg_type = genl_family;
48 hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
49 ghdr = snl_reserve_msg_object(nw, struct genlmsghdr);
50 if (__predict_false(ghdr == NULL))
51 return (NULL);
52 ghdr->cmd = genl_cmd;
53 nw->hdr = hdr;
54
55 return (hdr);
56}
57
58static struct snl_field_parser snl_fp_genl[] = {};
59
60#define SNL_DECLARE_GENL_PARSER(_name, _np) SNL_DECLARE_PARSER(_name,\
61 struct genlmsghdr, snl_fp_genl, _np)
62
63struct _snl_genl_ctrl_mcast_group {
64 uint32_t mcast_grp_id;
65 const char *mcast_grp_name;
66};
67
68struct _snl_genl_ctrl_mcast_groups {
69 uint32_t num_groups;
70 struct _snl_genl_ctrl_mcast_group **groups;
71};
72
73#define _OUT(_field) offsetof(struct _snl_genl_ctrl_mcast_group, _field)
74static struct snl_attr_parser _nla_p_getmc[] = {
75 {
76 .type = CTRL_ATTR_MCAST_GRP_NAME,
77 .off = _OUT(mcast_grp_name),
78 .cb = snl_attr_get_string,
79 },
80 {
81 .type = CTRL_ATTR_MCAST_GRP_ID,
82 .off = _OUT(mcast_grp_id),
83 .cb = snl_attr_get_uint32,
84 },
85};
86#undef _OUT
87SNL_DECLARE_ATTR_PARSER_EXT(_genl_ctrl_mc_parser,
88 sizeof(struct _snl_genl_ctrl_mcast_group), _nla_p_getmc, NULL);
89
90struct _getfamily_attrs {
91 uint16_t family_id;
92 const char *family_name;
93 struct _snl_genl_ctrl_mcast_groups mcast_groups;
94};
95
96#define _IN(_field) offsetof(struct genlmsghdr, _field)
97#define _OUT(_field) offsetof(struct _getfamily_attrs, _field)
98static struct snl_attr_parser _nla_p_getfam[] = {
99 {
100 .type = CTRL_ATTR_FAMILY_ID,
101 .off = _OUT(family_id),
102 .cb = snl_attr_get_uint16,
103 },
104 {
105 .type = CTRL_ATTR_FAMILY_NAME,
106 .off = _OUT(family_name),
107 .cb = snl_attr_get_string,
108 },
109 {
110 .type = CTRL_ATTR_MCAST_GROUPS,
111 .off = _OUT(mcast_groups),
112 .cb = snl_attr_get_parray,
113 .arg = &_genl_ctrl_mc_parser,
114 },
115};
116#undef _IN
117#undef _OUT
118SNL_DECLARE_GENL_PARSER(_genl_ctrl_getfam_parser, _nla_p_getfam);
119
120static bool
121_snl_get_genl_family_info(struct snl_state *ss, const char *family_name,
122 struct _getfamily_attrs *attrs)
123{
124 struct snl_writer nw;
125 struct nlmsghdr *hdr;
126
127 memset(attrs, 0, sizeof(*attrs));
128
129 snl_init_writer(ss, &nw);
130 snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY);
131 snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, family_name);
132 if ((hdr = snl_finalize_msg(&nw)) == NULL || !snl_send_message(ss, hdr))
133 return (false);
134
135 hdr = snl_read_reply(ss, hdr->nlmsg_seq);
136 if (hdr != NULL && hdr->nlmsg_type != NLMSG_ERROR) {
137 if (snl_parse_nlmsg(ss, hdr, &_genl_ctrl_getfam_parser, attrs))
138 return (true);
139 }
140
141 return (false);
142}
143
144static inline uint16_t
145snl_get_genl_family(struct snl_state *ss, const char *family_name)
146{
147 struct _getfamily_attrs attrs = {};
148
149 if (__predict_false(!_snl_get_genl_family_info(ss, family_name,
150 &attrs)))
151 return (0);
152 return (attrs.family_id);
153}
154
155static inline uint16_t
156snl_get_genl_mcast_group(struct snl_state *ss, const char *family_name,
157 const char *group_name, uint16_t *family_id)
158{
159 struct _getfamily_attrs attrs = {};
160
161 if (__predict_false(!_snl_get_genl_family_info(ss, family_name,
162 &attrs)))
163 return (0);
164 if (attrs.family_id == 0)
165 return (0);
166 if (family_id != NULL)
167 *family_id = attrs.family_id;
168 for (u_int i = 0; i < attrs.mcast_groups.num_groups; i++)
169 if (strcmp(attrs.mcast_groups.groups[i]->mcast_grp_name,
170 group_name) == 0)
171 return (attrs.mcast_groups.groups[i]->mcast_grp_id);
172 return (0);
173}
174
175#endif