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