bool CDiscoveryApp::fillDiscoveryResponse( void )
{
IP_array ip_array;
memset(&m_stDiscoveryResponse, 0, sizeof(DiscoveryResponse_Msg));
m_stDiscoveryResponse.m_uchMessageVersion=1;
m_stDiscoveryResponse.m_uchMessageType=2;
m_stDiscoveryResponse.m_unAnId=getANId();
memset(&ip_array, 0, sizeof(ip_array));
if (GetNetworkConfiguration(ip_array) < 0)
{
return false;
}
MatchIP_dev(ip_array);
get_default_gateway( NULL, NULL, 0 );
m_stDiscoveryResponse.m_ushCRC=computeCRC((uint8_t *)&m_stDiscoveryResponse,
(uint16_t)(sizeof(DiscoveryResponse_Msg)-sizeof(m_stDiscoveryResponse.m_ushCRC)));
print_DiscoveryResponse( );
return true;
}
void CDiscoveryApp::SetDefaulRoute(in_addr_t gw)
{
in_addr_t def_dest=inet_addr("0.0.0.0");
in_addr_t def_mask=inet_addr("0.0.0.0");
in_addr addr={0};
char szDevice [64];
switch( get_default_gateway( &addr.s_addr, szDevice, sizeof(szDevice) ) )
{
case DEFAULT_ETH_INTERF:
LOG("REPLACING DefaultGW [%s] on %s", inet_ntoa(addr), m_szEthInterf);
del_route(addr.s_addr);
set_route(def_dest, gw, def_mask);
break;
case DEFAULT_NOT_ETH_INTERF:
LOG("NOT REPLACING DefaultGW GW [%s] on %s", inet_ntoa(addr), szDevice );
break;
case DEFAULT_NOT_SET:
LOG("SETTING DefaultGW [%s] on %s", inet_ntoa(addr), m_szEthInterf);
set_route(def_dest, gw, def_mask);
break;
}
}
int packet_filter()
{
char *dev, *nextdev;
bpf_u_int32 mask;
bpf_u_int32 net;
struct bpf_program fp;
char filter_exp[] = "ip and not dst host 172.16.205.1";
char errbuf[PCAP_ERRBUF_SIZE];
struct pcap_pkthdr header;
const u_char *packet;
libnet_t *int_llif, *ext_llif;
struct ether_addr *t_hwaddr;
pthread_t ntid;
/* if ((dev = pcap_lookupdev(errbuf)) == NULL) {
fprintf(stderr, "Couldn't find default device: %s\n", errbuf);
return(2);
}
printf("Device: %s\n", dev);
*/
if (get_default_gateway(&def_gw) != 0) {
fprintf(stderr, "Couldn't get default gateway\n");
return(2);
}
printf("gw: %s\n", inet_ntoa(def_gw));
/* initialize handler/filter for external network interface */
dev = ext_ifname;
if (pcap_lookupnet(dev, &net, &mask, errbuf) == -1) {
fprintf(stderr, "Couldn't get netmask for the device %s\n", dev);
return(2);
}
printf("net: %s, mask %s\n", inet_ntoa(*(struct in_addr *)&net), inet_ntoa(*(struct in_addr *)&mask));
if ((ext_if = pcap_open_live(dev, BUFSIZ, 1, 1000, errbuf)) == NULL) {
fprintf(stderr, "Couldn't open device %s: %s\n", dev,errbuf);
return(2);
}
if(pcap_compile(ext_if, &fp, filter_exp, 0, net) == -1) {
fprintf(stderr, "Couldn't parse filter %s: %s\n", filter_exp, pcap_geterr(ext_if));
return(2);
}
if(pcap_setfilter(ext_if, &fp) == -1) {
fprintf(stderr, "Couldn't install filter %s: %s\n", filter_exp, pcap_geterr(ext_if));
return(2);
}
if ((ext_llif = libnet_init(LIBNET_LINK, ext_ifname, errbuf)) == 0) {
fprintf(stderr, "Couldn't open local network interface %s: %s\n", ext_ifname, errbuf);
return(2);
}
if ((*((u_int *)&ext_ip) = libnet_get_ipaddr4(ext_llif)) == -1) {
fprintf(stderr, "Couldn't get local ip address for %s \n", ext_ifname);
return(2);
}
if ((t_hwaddr = (struct ether_addr *)libnet_get_hwaddr(ext_llif)) == NULL) {
fprintf(stderr, "Couldn't get local network interface address for %s \n", ext_ifname);
return(2);
}
memcpy((u_char *)&ext_hwaddr, (u_char *)t_hwaddr, ETHER_ADDR_LEN);
libnet_destroy(ext_llif);
if (get_netmask(ext_ifname, &ext_mask) == -1) {
fprintf(stderr, "Couldn't get local netmask for %s \n", ext_ifname);
return(2);
}
printf("ext_ip : %s ", inet_ntoa(ext_ip) );
printf("ext_ip : %s\n", inet_ntoa(ext_mask));
/* initialize handler/filter for internal network interface */
dev = int_ifname;
if (pcap_lookupnet(dev, &net, &mask, errbuf) == -1) {
fprintf(stderr, "Couldn't get netmask for the device %s\n", dev);
return(2);
}
printf("net: %s, mask %s\n", inet_ntoa(*(struct in_addr *)&net), inet_ntoa(*(struct in_addr *)&mask));
if ((int_if = pcap_open_live(dev, BUFSIZ, 1, 1000, errbuf)) == NULL) {
fprintf(stderr, "Couldn't open device %s: %s\n", dev,errbuf);
return(2);
}
if(pcap_compile(int_if, &fp, filter_exp, 0, net) == -1) {
fprintf(stderr, "Couldn't parse filter %s: %s\n", filter_exp, pcap_geterr(int_if));
return(2);
}
if(pcap_setfilter(int_if, &fp) == -1) {
fprintf(stderr, "Couldn't install filter %s: %s\n", filter_exp, pcap_geterr(int_if));
return(2);
}
if ((int_llif = libnet_init(LIBNET_LINK, int_ifname, errbuf)) == 0) {
fprintf(stderr, "Couldn't open local network interface %s: %s\n", int_ifname, errbuf);
return(2);
}
if ((*((u_int *)&int_ip) = libnet_get_ipaddr4(int_llif)) == -1) {
fprintf(stderr, "Couldn't get local ip address for %s \n", int_ifname);
return(2);
}
if ((t_hwaddr = (struct ether_addr *)libnet_get_hwaddr(int_llif)) == NULL) {
fprintf(stderr, "Couldn't get local network interface address for %s \n", int_ifname);
return(2);
}
memcpy((u_char *)&int_hwaddr, (u_char *)t_hwaddr, ETHER_ADDR_LEN);
libnet_destroy(int_llif);
if (pthread_create(&ntid, NULL, clean_thread, NULL) != 0) {
fprintf(stderr, "Couldn't create thread\n");
}
if (pthread_create(&ntid, NULL, ext_thread, NULL) != 0) {
fprintf(stderr, "Couldn't create thread\n");
}
if(pcap_loop(int_if, -1, got_packet, (void *)FROM_INT) == -1) {
fprintf(stderr, "Couldn't filte packet %s: %s\n", filter_exp, pcap_geterr(int_if));
}
pcap_close(int_if);
return(0);
}
