ssh-proxy.py

 1#!/usr/bin/env python3
 2import os
 3import subprocess
 4import sys
 5from urllib.parse import urlparse
 6
 7proxy = next(os.environ[_] for _ in ("HTTP_PROXY", "HTTPS_PROXY") if _ in os.environ)
 8
 9parsed = urlparse(proxy)
10
11proxy_protocols = {
12    "http": "connect",
13    "https": "connect",
14    "socks": "5",
15    "socks5": "5",
16    "socks4": "4",
17    "socks4a": "4",
18}
19
20if parsed.scheme not in proxy_protocols:
21    raise TypeError('unsupported proxy protocol: "{}"'.format(parsed.scheme))
22
23def make_argv():
24    yield "nc"
25    if sys.platform in {'linux', 'cygwin'}:
26        # caveats: the built-in netcat of most linux distributions and cygwin support proxy type
27        # caveats: macOS built-in netcat command not supported proxy-type
28        yield "-X" # --proxy-type
29        # Supported protocols are 4 (SOCKS v4), 5 (SOCKS v5) and connect (HTTP proxy).
30        # Default SOCKS v5 is used.
31        yield proxy_protocols[parsed.scheme]
32    yield "-x" # --proxy
33    yield parsed.netloc # proxy-host:proxy-port
34    yield sys.argv[1] # host
35    yield sys.argv[2] # port
36
37subprocess.call(make_argv())