ftplib HTTP CONNECT

ftp_connect.py

#!/usr/bin/python

# This is a quick dirty python3 translation of https://code.activestate.com/recipes/577643-transparent-http-tunnel-for-python-sockets-to-be-u/
import socket

# Class that wraps a real socket and changes it to a HTTP tunnel whenever a connection is asked via the "CONNECT" method
class ProxySock :

    def __init__(self, socket, proxy_host, proxy_port) :

        # First, use the socket, without any change
        self.socket = socket

        # Create socket (use real one)
        self.proxy_host = proxy_host
        self.proxy_port = proxy_port

        # Copy attributes
        self.family = socket.family
        self.type = socket.type
        self.proto = socket.proto

    def connect(self, address) :

        # Store the real remote adress
        (self.host, self.port) = address
        # Try to connect to the proxy
        for (family, socktype, proto, canonname, sockaddr) in socket.getaddrinfo(
            self.proxy_host,
            self.proxy_port,
            0, 0, socket.SOL_TCP) :
            try:

                # Replace the socket by a connection to the proxy
                self.socket = socket.socket_formal(family, socktype, proto)
                self.socket.connect(sockaddr)

            except socket.error:
                if self.socket:
                    self.socket.close()
                self.socket = None
                continue
            break
        if not self.socket :
            raise socket.error

        # Ask him to create a tunnel connection to the target host/port
        self.socket.send((f"CONNECT {self.host}:{self.port} HTTP/1.1\r\n"
                          f"Host: {self.host}:{self.port}\r\n\r\n").encode())

        # Get the response
        resp = self.socket.recv(4096)

        # Parse the response
        parts = resp.split()

        # Not 200 ?
        if parts[1] != b"200" :
            raise Exception(f"Error response from Proxy server : {resp}")

    # Wrap all methods of inner socket, without any change
    def accept(self) :
        return self.socket.accept()

    def bind(self, *args) :
        return self.socket.bind(*args)

    def close(self) :
        return self.socket.close()

    def fileno(self) :
        return self.socket.fileno()


    def getsockname(self) :
        return self.socket.getsockname()

    def getsockopt(self, *args) :
        return self.socket.getsockopt(*args)

    def listen(self, *args) :
        return self.socket.listen(*args)

    def makefile(self, *args, **kwargs) :
        return self.socket.makefile(*args, **kwargs)

    def recv(self, *args) :
        return self.socket.recv(*args)

    def recvfrom(self, *args) :
        return self.socket.recvfrom(*args)

    def recvfrom_into(self, *args) :
        return self.socket.recvfrom_into(*args)

    def recv_into(self, *args) :
        return self.socket.recv_into(buffer, *args)

    def send(self, *args) :
        return self.socket.send(*args)

    def sendall(self, *args) :
        return self.socket.sendall(*args)

    def sendto(self, *args) :
        return self.socket.sendto(*args)

    def setblocking(self, *args) :
        return self.socket.setblocking(*args)

    def settimeout(self, *args) :
        return self.socket.settimeout(*args)

    def gettimeout(self) :
        return self.socket.gettimeout()

    def setsockopt(self, *args):
        return self.socket.setsockopt(*args)

    def shutdown(self, *args):
        return self.socket.shutdown(*args)

    # Return the (host, port) of the actual target, not the proxy gateway
    def getpeername(self) :
        return (self.host, self.port)

# Install a proxy, by changing the method socket.socket()
def setup_http_proxy(proxy_host, proxy_port) :

    # New socket constructor that returns a ProxySock, wrapping a real socket
    def socket_proxy(af, socktype, proto) :

        # Create a socket, old school :
        sock = socket.socket_formal(af, socktype, proto)

        # Wrap it within a proxy socket
        return ProxySock(
            sock,
            proxy_host,
            proxy_port)

    # Replace the "socket" method by our custom one
    socket.socket_formal = socket.socket
    socket.socket = socket_proxy

# Imports
from ftplib import FTP

# Constants
PROXY_HOST="proxy.host"
PROXY_PORT=80
FTP_HOST="ftphost.net"
FTP_USER="anonymous"
FTP_PASS="anonymous"
FTP_FILE="/path.to/file.txt"
FTP_DIR="/path/to/folder/"

# Install the proxy on the "socket" module
setup_http_proxy(
    PROXY_HOST,
    PROXY_PORT)
ftp = FTP(FTP_HOST)