int connect_dest(char *host_name, char *port)
{
struct hostent *host;
struct servent *service;
struct sockaddr_in addr;
int sock;
addr.sin_family = AF_INET;
if ((addr.sin_addr.s_addr = inet_addr(host_name)) == (in_addr_t) -1) {
if ((host = gethostbyname(host_name)) != NULL) {
memcpy((char *) &addr.sin_addr, host->h_addr, host->h_length);
} else {
fprintf(stderr, "unknown host %s\n", host_name);
return -1;
}
}
if ((addr.sin_port = htons(atoi(port))) == 0) {
if ((service = getservbyname(port, "tcp")) != NULL) {
addr.sin_port = service->s_port;
} else {
fprintf(stderr, "unrecognized port %s\n", port);
return -1;
}
}
check((sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)), "socket", -1);
show_addr("Connecting to", &addr);
check(connect(sock, (struct sockaddr *)&addr, sizeof(addr)), "connect", -1);
return sock;
}
void got_packet (u_char *args, const struct pcap_pkthdr *header, const u_char *packet) {
static int count = 1;
int etype=0, protocol=0;
int size_ip, size_tcp, size_total;
const struct sniff_ethernet * ethernet;
const struct sniff_ip * ip;
const struct sniff_tcp *tcp;
ethernet = (struct sniff_ethernet*)(packet);
ip = (struct sniff_ip*)(packet + 14);
size_ip = IP_HL(ip);
tcp = (struct sniff_tcp*)(packet + 14 + size_ip);
size_tcp = TH_OFF(tcp)*4;
size_total = ntohs(ip->ip_len) + 14;
printf("\ncount : %d\n", count);
count++;
printf("------------------------------\n");
etype = show_addr(packet);
if (etype == IPV4) {
protocol = show_ipv4_ip(packet);
if (protocol == TCP) {
show_port(packet);
if (size_total != (size_ip + size_tcp + 14)) {
printf("------------------------------\n");
show_data(args, header, packet, *(packet+size_total), size_total);
printf("------------------------------\n");
}
} else if (protocol == UDP) {
show_port(packet);
printf("------------------------------\n");
show_data(args, header, packet, 42, size_total);
printf("------------------------------\n");
}
printf("------------------------------\n");
} else if (etype == ARP) {
show_ark_ip(packet);
}
}
