1#include <stdio.h>
2#include <stdlib.h>
3#include <unistd.h>
4#include <time.h>
5#include <arpa/inet.h>
6
7#include <libmnl/libmnl.h>
8#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
9
10#include <linux/netfilter/nf_conntrack_tcp.h>
11
12int main(void)
13{
14	struct mnl_socket *nl;
15	struct nlmsghdr *nlh;
16	struct nfgenmsg *nfh;
17	char buf[MNL_SOCKET_BUFFER_SIZE];
18	unsigned int seq, portid;
19	int ret;
20
21	nl = mnl_socket_open(NETLINK_NETFILTER);
22	if (nl == NULL) {
23		perror("mnl_socket_open");
24		exit(EXIT_FAILURE);
25	}
26
27	if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
28		perror("mnl_socket_bind");
29		exit(EXIT_FAILURE);
30	}
31	portid = mnl_socket_get_portid(nl);
32
33	nlh = mnl_nlmsg_put_header(buf);
34	nlh->nlmsg_type = (NFNL_SUBSYS_CTNETLINK << 8) | IPCTNL_MSG_CT_DELETE;
35	nlh->nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
36	nlh->nlmsg_seq = seq = time(NULL);
37
38	nfh = mnl_nlmsg_put_extra_header(nlh, sizeof(struct nfgenmsg));
39	nfh->nfgen_family = AF_INET;
40	nfh->version = NFNETLINK_V0;
41	nfh->res_id = 0;
42
43	ret = mnl_socket_sendto(nl, nlh, nlh->nlmsg_len);
44	if (ret == -1) {
45		perror("mnl_socket_recvfrom");
46		exit(EXIT_FAILURE);
47	}
48
49	ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
50	while (ret > 0) {
51		ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL);
52		if (ret <= MNL_CB_STOP)
53			break;
54		ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
55	}
56	if (ret == -1) {
57		perror("mnl_socket_recvfrom");
58		exit(EXIT_FAILURE);
59	}
60
61	mnl_socket_close(nl);
62
63	return 0;
64}
65