]>
Commit | Line | Data |
---|---|---|
f043759d RA |
1 | /* |
2 | * msg.c Messaging (netlink) helper functions. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | * | |
9 | * Authors: Richard Alpe <richard.alpe@ericsson.com> | |
10 | */ | |
11 | ||
12 | #include <stdio.h> | |
13 | #include <time.h> | |
14 | #include <errno.h> | |
15 | ||
16 | #include <linux/tipc_netlink.h> | |
17 | #include <linux/tipc.h> | |
18 | #include <linux/genetlink.h> | |
19 | #include <libmnl/libmnl.h> | |
20 | ||
21 | #include "msg.h" | |
22 | ||
23 | int parse_attrs(const struct nlattr *attr, void *data) | |
24 | { | |
25 | const struct nlattr **tb = data; | |
26 | int type = mnl_attr_get_type(attr); | |
27 | ||
28 | tb[type] = attr; | |
29 | ||
30 | return MNL_CB_OK; | |
31 | } | |
32 | ||
33 | static int family_id_cb(const struct nlmsghdr *nlh, void *data) | |
34 | { | |
35 | struct nlattr *tb[CTRL_ATTR_MAX + 1] = {}; | |
36 | struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh); | |
37 | int *id = data; | |
38 | ||
39 | mnl_attr_parse(nlh, sizeof(*genl), parse_attrs, tb); | |
40 | if (!tb[CTRL_ATTR_FAMILY_ID]) | |
41 | return MNL_CB_ERROR; | |
42 | ||
43 | *id = mnl_attr_get_u16(tb[CTRL_ATTR_FAMILY_ID]); | |
44 | ||
45 | return MNL_CB_OK; | |
46 | } | |
47 | ||
48 | static struct mnl_socket *msg_send(struct nlmsghdr *nlh) | |
49 | { | |
50 | int ret; | |
51 | struct mnl_socket *nl; | |
52 | ||
53 | nl = mnl_socket_open(NETLINK_GENERIC); | |
54 | if (nl == NULL) { | |
55 | perror("mnl_socket_open"); | |
56 | return NULL; | |
57 | } | |
58 | ||
59 | ret = mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID); | |
60 | if (ret < 0) { | |
61 | perror("mnl_socket_bind"); | |
62 | return NULL; | |
63 | } | |
64 | ||
65 | ret = mnl_socket_sendto(nl, nlh, nlh->nlmsg_len); | |
66 | if (ret < 0) { | |
67 | perror("mnl_socket_send"); | |
68 | return NULL; | |
69 | } | |
70 | ||
71 | return nl; | |
72 | } | |
73 | ||
74 | static int msg_recv(struct mnl_socket *nl, mnl_cb_t callback, void *data, int seq) | |
75 | { | |
76 | int ret; | |
77 | unsigned int portid; | |
78 | char buf[MNL_SOCKET_BUFFER_SIZE]; | |
79 | ||
80 | portid = mnl_socket_get_portid(nl); | |
81 | ||
82 | ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); | |
83 | while (ret > 0) { | |
84 | ret = mnl_cb_run(buf, ret, seq, portid, callback, data); | |
85 | if (ret <= 0) | |
86 | break; | |
87 | ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); | |
88 | } | |
89 | if (ret == -1) | |
90 | perror("error"); | |
91 | ||
92 | mnl_socket_close(nl); | |
93 | ||
94 | return ret; | |
95 | } | |
96 | ||
97 | static int msg_query(struct nlmsghdr *nlh, mnl_cb_t callback, void *data) | |
98 | { | |
99 | unsigned int seq; | |
100 | struct mnl_socket *nl; | |
101 | ||
102 | seq = time(NULL); | |
103 | nlh->nlmsg_seq = seq; | |
104 | ||
105 | nl = msg_send(nlh); | |
106 | if (!nl) | |
107 | return -ENOTSUP; | |
108 | ||
109 | return msg_recv(nl, callback, data, seq); | |
110 | } | |
111 | ||
112 | static int get_family(void) | |
113 | { | |
114 | int err; | |
115 | int nl_family; | |
116 | struct nlmsghdr *nlh; | |
117 | struct genlmsghdr *genl; | |
118 | char buf[MNL_SOCKET_BUFFER_SIZE]; | |
119 | ||
120 | nlh = mnl_nlmsg_put_header(buf); | |
121 | nlh->nlmsg_type = GENL_ID_CTRL; | |
122 | nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; | |
123 | ||
124 | genl = mnl_nlmsg_put_extra_header(nlh, sizeof(struct genlmsghdr)); | |
125 | genl->cmd = CTRL_CMD_GETFAMILY; | |
126 | genl->version = 1; | |
127 | ||
aab3661b | 128 | mnl_attr_put_u16(nlh, CTRL_ATTR_FAMILY_ID, GENL_ID_CTRL); |
f043759d RA |
129 | mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, TIPC_GENL_V2_NAME); |
130 | ||
131 | if ((err = msg_query(nlh, family_id_cb, &nl_family))) | |
132 | return err; | |
133 | ||
134 | return nl_family; | |
135 | } | |
136 | ||
137 | int msg_doit(struct nlmsghdr *nlh, mnl_cb_t callback, void *data) | |
138 | { | |
139 | nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; | |
140 | return msg_query(nlh, callback, data); | |
141 | } | |
142 | ||
143 | int msg_dumpit(struct nlmsghdr *nlh, mnl_cb_t callback, void *data) | |
144 | { | |
145 | nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; | |
146 | return msg_query(nlh, callback, data); | |
147 | } | |
148 | ||
149 | struct nlmsghdr *msg_init(char *buf, int cmd) | |
150 | { | |
151 | int family; | |
152 | struct nlmsghdr *nlh; | |
153 | struct genlmsghdr *genl; | |
154 | ||
155 | family = get_family(); | |
156 | if (family <= 0) { | |
157 | fprintf(stderr, | |
158 | "Unable to get TIPC nl family id (module loaded?)\n"); | |
159 | return NULL; | |
160 | } | |
161 | ||
162 | nlh = mnl_nlmsg_put_header(buf); | |
163 | nlh->nlmsg_type = family; | |
164 | ||
165 | genl = mnl_nlmsg_put_extra_header(nlh, sizeof(struct genlmsghdr)); | |
166 | genl->cmd = cmd; | |
167 | genl->version = 1; | |
168 | ||
169 | return nlh; | |
170 | } |