root/dump/ftpexe.py

from ftplib import FTP

import os
import sys
import socket
import random

class dFTP(FTP):
    def __init__(self):
        FTP.__init__(self)
        self.nat_host = None
        self.nat_port_range = None

    def makeport(self):
        '''Create a new socket and send a PORT command for it.'''
        msg = "getaddrinfo returns an empty list"
        sock = None
        for res in socket.getaddrinfo(None, 0, self.af, socket.SOCK_STREAM, 0, socket.AI_PASSIVE):
            af, socktype, proto, canonname, sa = res
            ports = list(filter(lambda port: ((port >> 4) & 0xf) != 0, range(self.nat_port_range[0], self.nat_port_range[1])))
            random.shuffle(ports)
            for port in ports:
                try:
                    sock = socket.socket(af, socktype, proto)
                    sa = tuple([sa[0], port])
                    sock.bind(sa)
                except socket.error as msg:
                    if sock:
                        sock.close()
                    sock = None
                    continue
                break
        if not sock:
            raise socket.error(msg)
        sock.listen(1)
        port = sock.getsockname()[1] # Get proper port
        host = socket.gethostbyname(self.nat_host)
        if self.af == socket.AF_INET:
            resp = self.sendport(host, port)
        else:
            resp = self.sendeprt(host, port)
        return sock

    def retrbinary(self, cmd, callback, blocksize=8192, rest=None):
        conn = self.transfercmd(cmd, rest)
        while 1:
            data = conn.recv(blocksize)
            if not data:
                break
            callback(data)
        conn.close()
        return self.voidresp()
                
def download():
    '''ftp via nat program.
    Usage: ftpexe [options]
    -v verbose
    -H nat host
    -R nat port-range
    -s host:port
    -u user
    -p password 
    -f file
    -b send TYPE I
    '''

    verbose = 0
    nat_host = None
    nat_port_range = None
    host = None
    port = None
    user = None
    password = None
    rfile = None
    binary = False

    i = 1
    while i < len(sys.argv):
        print("ARG %s" % (sys.argv[i]))
        if sys.argv[i] == '-v':
            verbose = verbose+1
        elif sys.argv[i] == '-H':
            i=i+1
            nat_host = sys.argv[i]
        elif sys.argv[i] == '-R':
            i=i+1
            nat_port_range = sys.argv[i]
        elif sys.argv[i] == '-s':
            i=i+1
            host = sys.argv[i]
        elif sys.argv[i] == '-u':
            i=i+1
            user = sys.argv[i]
        elif sys.argv[i] == '-f':
            i=i+1
            rfile = sys.argv[i]
        elif sys.argv[i] == '-b':
            binary=True
        elif sys.argv[i] == '-h':
            print(download.__doc__)
            sys.exit(0)
        i=i+1

    if not host or not nat_port_range or not nat_host or not rfile:
        print(download.__doc__)
        sys.exit(0)
        
    off = host.find(':')
    if off != -1:
        port = int(host[off+1:])
        host = host[:off]
    else: 
        port = 21
    print("host %s %i" % (host, port))

    if nat_port_range:
        x = nat_port_range.find('-')
        min_port = int(nat_port_range[:x])
        max_port = int(nat_port_range[x+1:])
    print("nat host %s port range %s to %s" % (nat_host, min_port, max_port))    

    if not user:
        user = 'anonymous'
        password = 'guest'
    print("user %s pass %s" % (user, password))

    ftp = dFTP()
    ftp.set_debuglevel(verbose)
    ftp.connect(host=host, port=port)
    ftp.nat_host = nat_host
    ftp.nat_port_range = [min_port, max_port]

    ftp.login(user, password)
    lfile=open(rfile, 'wb')
    ftp.set_pasv(not ftp.passiveserver)
    if binary:
        ftp.voidcmd('TYPE I')
    ftp.retrbinary('RETR ' + rfile, \
                           lfile.write, 1024)
    ftp.quit()


if __name__ == '__main__':
    download()