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12#include <stdlib.h>
13#include <stdbool.h>
14#include <string.h>
15#include <errno.h>
16#include <unistd.h>
17#include <libmnl/libmnl.h>
18#include <linux/genetlink.h>
19
20#include "libnetlink.h"
21#include "mnl_utils.h"
22#include "utils.h"
23#include "mnlg.h"
24
25struct mnlg_socket {
26 struct mnl_socket *nl;
27 char *buf;
28 uint32_t id;
29 uint8_t version;
30 unsigned int seq;
31};
32
33int mnlg_socket_send(struct mnlu_gen_socket *nlg, const struct nlmsghdr *nlh)
34{
35 return mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
36}
37
38struct group_info {
39 bool found;
40 uint32_t id;
41 const char *name;
42};
43
44static int parse_mc_grps_cb(const struct nlattr *attr, void *data)
45{
46 const struct nlattr **tb = data;
47 int type = mnl_attr_get_type(attr);
48
49 if (mnl_attr_type_valid(attr, CTRL_ATTR_MCAST_GRP_MAX) < 0)
50 return MNL_CB_OK;
51
52 switch (type) {
53 case CTRL_ATTR_MCAST_GRP_ID:
54 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
55 return MNL_CB_ERROR;
56 break;
57 case CTRL_ATTR_MCAST_GRP_NAME:
58 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
59 return MNL_CB_ERROR;
60 break;
61 }
62 tb[type] = attr;
63 return MNL_CB_OK;
64}
65
66static void parse_genl_mc_grps(struct nlattr *nested,
67 struct group_info *group_info)
68{
69 struct nlattr *pos;
70 const char *name;
71
72 mnl_attr_for_each_nested(pos, nested) {
73 struct nlattr *tb[CTRL_ATTR_MCAST_GRP_MAX + 1] = {};
74
75 mnl_attr_parse_nested(pos, parse_mc_grps_cb, tb);
76 if (!tb[CTRL_ATTR_MCAST_GRP_NAME] ||
77 !tb[CTRL_ATTR_MCAST_GRP_ID])
78 continue;
79
80 name = mnl_attr_get_str(tb[CTRL_ATTR_MCAST_GRP_NAME]);
81 if (strcmp(name, group_info->name) != 0)
82 continue;
83
84 group_info->id = mnl_attr_get_u32(tb[CTRL_ATTR_MCAST_GRP_ID]);
85 group_info->found = true;
86 }
87}
88
89static int get_group_id_attr_cb(const struct nlattr *attr, void *data)
90{
91 const struct nlattr **tb = data;
92 int type = mnl_attr_get_type(attr);
93
94 if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
95 return MNL_CB_ERROR;
96
97 if (type == CTRL_ATTR_MCAST_GROUPS &&
98 mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
99 return MNL_CB_ERROR;
100 tb[type] = attr;
101 return MNL_CB_OK;
102}
103
104static int get_group_id_cb(const struct nlmsghdr *nlh, void *data)
105{
106 struct group_info *group_info = data;
107 struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
108 struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
109
110 mnl_attr_parse(nlh, sizeof(*genl), get_group_id_attr_cb, tb);
111 if (!tb[CTRL_ATTR_MCAST_GROUPS])
112 return MNL_CB_ERROR;
113 parse_genl_mc_grps(tb[CTRL_ATTR_MCAST_GROUPS], group_info);
114 return MNL_CB_OK;
115}
116
117int mnlg_socket_group_add(struct mnlu_gen_socket *nlg, const char *group_name)
118{
119 struct nlmsghdr *nlh;
120 struct group_info group_info;
121 int err;
122
123 nlh = _mnlu_gen_socket_cmd_prepare(nlg, CTRL_CMD_GETFAMILY,
124 NLM_F_REQUEST | NLM_F_ACK,
125 GENL_ID_CTRL, 1);
126
127 mnl_attr_put_u16(nlh, CTRL_ATTR_FAMILY_ID, nlg->family);
128
129 err = mnlg_socket_send(nlg, nlh);
130 if (err < 0)
131 return err;
132
133 group_info.found = false;
134 group_info.name = group_name;
135 err = mnlu_gen_socket_recv_run(nlg, get_group_id_cb, &group_info);
136 if (err < 0)
137 return err;
138
139 if (!group_info.found) {
140 errno = ENOENT;
141 return -1;
142 }
143
144 err = mnl_socket_setsockopt(nlg->nl, NETLINK_ADD_MEMBERSHIP,
145 &group_info.id, sizeof(group_info.id));
146 if (err < 0)
147 return err;
148
149 return 0;
150}
151
152int mnlg_socket_get_fd(struct mnlu_gen_socket *nlg)
153{
154 return mnl_socket_get_fd(nlg->nl);
155}
156
