I want to ask, how to spoof an IP address, but without any external modules? Until now I've been using Scapy module, but I want to make it on my own, see how it is done and maybe learn something new. Here is the code with Scapy module:
from scapy.all import *
SPOOFED_PACKET = IP(src=SRC_IP, dst=DST_IP) / TCP(sport=SRC_PORT, dport=DST_PORT) / PAYLOAD
send(SPOOFED_PACKET)
"""Demonstrates how to construct and send raw Ethernet packets on the
network.
You probably need root privs to be able to bind to the network interface,
e.g.:
$ sudo python sendeth.py
"""
from socket import *
def sendeth(src, dst, eth_type, payload, interface = "eth0"):
"""Send raw Ethernet packet on interface."""
assert(len(src) == len(dst) == 6) # 48-bit ethernet addresses
assert(len(eth_type) == 2) # 16-bit ethernet type
s = socket(AF_PACKET, SOCK_RAW)
# From the docs: "For raw packet
# sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])"
s.bind((interface, 0))
return s.send(src + dst + eth_type + payload)
if __name__ == "__main__":
print("Sent %d-byte Ethernet packet on eth0" %
sendeth("\xFE\xED\xFA\xCE\xBE\xEF",
"\xFE\xED\xFA\xCE\xBE\xEF",
"\x7A\x05",
"hello"))
To include an IPv4 header:
"""Demonstrates how to construct and send raw Ethernet packets on the
network.
You probably need root privs to be able to bind to the network interface,
e.g.:
$ sudo python sendeth.py
"""
from socket import *
def sendeth(ethernet_packet, payload, interface = "eth0"):
"""Send raw Ethernet packet on interface."""
s = socket(AF_PACKET, SOCK_RAW)
# From the docs: "For raw packet
# sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])"
s.bind((interface, 0))
return s.send(ethernet_packet + payload)
def pack(byte_sequence):
"""Convert list of bytes to byte string."""
return b"".join(map(chr, byte_sequence))
if __name__ == "__main__":
# Note that this example contains HARDCODED packets, meaning that
# it will ONLY work on the system it was designed for.
# I got these values by sending a ping while running Wireshark.
# You can do so yourself. Another way to construct these manually is to use
# the impacket library (sudo pip install impacket)
# src=fe:ed:fa:ce:be:ef, dst=52:54:00:12:35:02, type=0x0800 (IP)
ethernet_packet = [0x52, 0x54, 0x00, 0x12, 0x35, 0x02, 0xfe, 0xed, 0xfa,
0xce, 0xbe, 0xef, 0x08, 0x00]
# src=10.0.2.15, dst=195.88.54.16 (vg.no), checksum, etc.
ipv4_header = [0x45, 0x00, 0x00, 0x54, 0x05, 0x9f, 0x40, 0x00, 0x40, 0x01,
0x2f, 0x93, 0x0a, 0x00, 0x02, 0x0f, 0xc3, 0x58, 0x36, 0x10]
# echo (ping) request, checksum 2b45, etc
icmp_ping = [0x08, 0x00, 0x2b, 0x45, 0x11, 0x22, 0x00, 0x02, 0xa9, 0xf4, 0x5c,
0x53, 0x00, 0x00, 0x00, 0x00, 0xf5, 0x7b, 0x01, 0x00, 0x00, 0x00,
0x00, 0x00, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e,
0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37]
payload = "".join(map(chr, ipv4_header + icmp_ping))
# Construct Ethernet packet with an IPv4 ICMP PING request as payload
r = sendeth(pack(ethernet_packet),
pack(ipv4_header + icmp_ping))
print("Sent Ethernet w/IPv4 ICMP PING payload of length %d bytes" % r)