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/*
* (C) 2009-2010 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <libmnl/libmnl.h>
#include <linux/if.h>
#include <linux/if_link.h>
#include <linux/rtnetlink.h>
static int data_attr_cb(const struct nlattr *attr, void *data)
{
const struct nlattr **tb = data;
int type = mnl_attr_get_type(attr);
/* skip unsupported attribute in user-space */
if (mnl_attr_type_valid(attr, IFLA_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case IFLA_MTU:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
case IFLA_IFNAME:
if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) {
perror("mnl_attr_validate2");
return MNL_CB_ERROR;
}
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static int data_cb(const struct nlmsghdr *nlh, void *data)
{
struct nlattr *tb[IFLA_MAX+1] = {};
struct ifinfomsg *ifm = mnl_nlmsg_get_payload(nlh);
printf("index=%d type=%d flags=%d family=%d ",
ifm->ifi_index, ifm->ifi_type,
ifm->ifi_flags, ifm->ifi_family);
if (ifm->ifi_flags & IFF_RUNNING)
printf("[RUNNING] ");
else
printf("[NOT RUNNING] ");
mnl_attr_parse(nlh, sizeof(*ifm), data_attr_cb, tb);
if (tb[IFLA_MTU]) {
printf("mtu=%d ", mnl_attr_get_u32(tb[IFLA_MTU]));
}
if (tb[IFLA_IFNAME]) {
printf("name=%s", mnl_attr_get_str(tb[IFLA_IFNAME]));
}
printf("\n");
return MNL_CB_OK;
}
int main(void)
{
struct mnl_socket *nl;
char buf[MNL_SOCKET_BUFFER_SIZE];
int ret;
nl = mnl_socket_open(NETLINK_ROUTE);
if (nl == NULL) {
perror("mnl_socket_open");
exit(EXIT_FAILURE);
}
if (mnl_socket_bind(nl, RTMGRP_LINK, MNL_SOCKET_AUTOPID) < 0) {
perror("mnl_socket_bind");
exit(EXIT_FAILURE);
}
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
while (ret > 0) {
ret = mnl_cb_run(buf, ret, 0, 0, data_cb, NULL);
if (ret <= 0)
break;
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
}
if (ret == -1) {
perror("error");
exit(EXIT_FAILURE);
}
mnl_socket_close(nl);
return 0;
}
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