void send_packets(PacketSender& sender) {
// ICMPs are icmp-requests by default
IP ip = IP(addr, iface.addresses().ip_addr) / ICMP();
ICMP& icmp = ip.rfind_pdu<ICMP>();
icmp.sequence(sequence);
// We'll find at most 20 hops.
for (auto i = 1; i <= 20; ++i) {
// Set this ICMP id
icmp.id(i);
// Set the time-to-live option
ip.ttl(i);
// Critical section
{
lock_guard<mutex> _(lock);
ttls[i] = i;
}
sender.send(ip);
// Give it a little time
sleep_for(milliseconds(100));
}
running = false;
sender.send(ip);
}
// Send syns to the given ip address, using the destination ports provided.
void send_syns(const NetworkInterface &iface, IPv4Address dest_ip, const vector<string> &ips) {
// Retrieve the addresses.
NetworkInterface::Info info = iface.addresses();
PacketSender sender;
// Allocate the IP PDU
IP ip = IP(dest_ip, info.ip_addr) / TCP();
// Get the reference to the TCP PDU
TCP &tcp = ip.rfind_pdu<TCP>();
// Set the SYN flag on.
tcp.set_flag(TCP::SYN, 1);
// Just some random port.
tcp.sport(1337);
cout << "Sending SYNs..." << endl;
for(vector<string>::const_iterator it = ips.begin(); it != ips.end(); ++it) {
// Set the new port and send the packet!
tcp.dport(atoi(it->c_str()));
sender.send(ip);
}
// Wait 1 second.
sleep(1);
/* Special packet to indicate that we're done. This will be sniffed
* by our function, which will in turn return false.
*/
tcp.set_flag(TCP::RST, 1);
// Pretend we're the scanned host...
ip.src_addr(dest_ip);
// We use an ethernet pdu, otherwise the kernel will drop it.
EthernetII eth = EthernetII(info.hw_addr, info.hw_addr) / ip;
sender.send(eth, iface);
}
void test2_sendpkt() {
PacketSender sender;
IP
pkt = IP("192.168.0.1") / TCP(22) / RawPDU(randomStr().c_str());
std::cout << std::endl;
for (;;) {
sender.send(pkt);
std::cout << ".";
}
}
void send_packets(PacketSender &sender) {
// ICMPs are icmp-requests by default
IP ip = IP(addr, iface.addresses().ip_addr) / ICMP();
// We'll find at most 10 hops.
for(auto i = 1; i <= 10; ++i) {
// Set this "unique" id
ip.id(i);
// Set the time-to-live option
ip.ttl(i);
// Critical section
{
std::lock_guard<std::mutex> _(lock);
ttls[i] = i;
}
sender.send(ip);
// Give him a little time
std::this_thread::sleep_for(std::chrono::milliseconds(100));
}
running = false;
sender.send(ip);
}
bool callback(const PDU &pdu)
{
// The packet probably looks like this:
//
// EthernetII / IP / UDP / RawPDU
//
// So we retrieve each layer, and construct a
// DNS PDU from the RawPDU layer contents.
EthernetII eth = pdu.rfind_pdu<EthernetII>();
IP ip = eth.rfind_pdu<IP>();
UDP udp = ip.rfind_pdu<UDP>();
DNS dns = udp.rfind_pdu<RawPDU>().to<DNS>();
// Is it a DNS query?
if(dns.type() == DNS::QUERY) {
// Let's see if there's any query for an "A" record.
for(const auto &query : dns.queries()) {
if(query.type() == DNS::A) {
// Here's one! Let's add an answer.
dns.add_answer(
DNS::Resource(
query.dname(),
"127.0.0.1",
DNS::A,
query.query_class(),
// 777 is just a random TTL
777
)
);
}
}
// Have we added some answers?
if(dns.answers_count() > 0) {
// It's a response now
dns.type(DNS::RESPONSE);
// Recursion is available(just in case)
dns.recursion_available(1);
// Build our packet
auto pkt = EthernetII(eth.src_addr(), eth.dst_addr()) /
IP(ip.src_addr(), ip.dst_addr()) /
UDP(udp.sport(), udp.dport()) /
dns;
// Send it!
sender.send(pkt);
}
}
return true;
}
