conntrack_grp_create.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <arpa/inet.h>

#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_tcp.h>

int main(void)
{
        int ret;
        struct nfct_handle *h;
        struct nf_conntrack *ct;

        ct = nfct_new();
        if (!ct) {
                perror("nfct_new");
                return 0;
        }

        struct nfct_attr_grp_ipv4 grp_ipv4 = {
                .src = inet_addr("1.1.1.1"),
                .dst = inet_addr("2.2.2.2")
        };
        nfct_set_attr_grp(ct, ATTR_GRP_ORIG_IPV4, &grp_ipv4);

        struct nfct_attr_grp_port grp_port = {
                .sport = htons(20),
                .dport = htons(10)
        };
        nfct_set_attr_grp(ct, ATTR_GRP_ORIG_PORT, &grp_port);
        nfct_set_attr_u8(ct, ATTR_L4PROTO, IPPROTO_TCP);

        nfct_setobjopt(ct, NFCT_SOPT_SETUP_REPLY);

        nfct_set_attr_u8(ct, ATTR_TCP_STATE, TCP_CONNTRACK_SYN_SENT);
        nfct_set_attr_u32(ct, ATTR_TIMEOUT, 100);
        nfct_set_attr(ct, ATTR_HELPER_NAME, "ftp");

        h = nfct_open(CONNTRACK, 0);
        if (!h) {
                perror("nfct_open");
                return -1;
        }

        ret = nfct_query(h, NFCT_Q_CREATE, ct);

        printf("TEST: create conntrack ");
        if (ret == -1) 
                printf("(%d)(%s)\n", ret, strerror(errno));
        else
                printf("(OK)\n");

        nfct_close(h);

        ret == -1 ? exit(EXIT_FAILURE) : exit(EXIT_SUCCESS);
}