1 /* This example is placed in the public domain. */
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <unistd.h>
5 #include <string.h>
6 #include <time.h>
7
8 #include <libmnl/libmnl.h>
9 #include <linux/if.h>
10 #include <linux/if_link.h>
11 #include <linux/rtnetlink.h>
12
main(int argc,char * argv[])13 int main(int argc, char *argv[])
14 {
15 struct mnl_socket *nl;
16 char buf[MNL_SOCKET_BUFFER_SIZE];
17 struct nlmsghdr *nlh;
18 struct ifinfomsg *ifm;
19 int ret;
20 unsigned int seq, portid, change = 0, flags = 0;
21
22 if (argc != 3) {
23 printf("Usage: %s [ifname] [up|down]\n", argv[0]);
24 exit(EXIT_FAILURE);
25 }
26
27 if (strncasecmp(argv[2], "up", strlen("up")) == 0) {
28 change |= IFF_UP;
29 flags |= IFF_UP;
30 } else if (strncasecmp(argv[2], "down", strlen("down")) == 0) {
31 change |= IFF_UP;
32 flags &= ~IFF_UP;
33 } else {
34 fprintf(stderr, "%s is not `up' nor `down'\n", argv[2]);
35 exit(EXIT_FAILURE);
36 }
37
38 nlh = mnl_nlmsg_put_header(buf);
39 nlh->nlmsg_type = RTM_NEWLINK;
40 nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
41 nlh->nlmsg_seq = seq = time(NULL);
42 ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm));
43 ifm->ifi_family = AF_UNSPEC;
44 ifm->ifi_change = change;
45 ifm->ifi_flags = flags;
46
47 mnl_attr_put_str(nlh, IFLA_IFNAME, argv[1]);
48
49 nl = mnl_socket_open(NETLINK_ROUTE);
50 if (nl == NULL) {
51 perror("mnl_socket_open");
52 exit(EXIT_FAILURE);
53 }
54
55 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
56 perror("mnl_socket_bind");
57 exit(EXIT_FAILURE);
58 }
59 portid = mnl_socket_get_portid(nl);
60
61 mnl_nlmsg_fprintf(stdout, nlh, nlh->nlmsg_len,
62 sizeof(struct ifinfomsg));
63
64 if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
65 perror("mnl_socket_sendto");
66 exit(EXIT_FAILURE);
67 }
68
69 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
70 if (ret == -1) {
71 perror("mnl_socket_recvfrom");
72 exit(EXIT_FAILURE);
73 }
74
75 ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL);
76 if (ret == -1){
77 perror("mnl_cb_run");
78 exit(EXIT_FAILURE);
79 }
80
81 mnl_socket_close(nl);
82
83 return 0;
84 }
85