python-proxy

HTTP/Socks/Shadowsocks/Redirect asynchronous tunnel proxy implemented in Python3 asyncio.

Features

• Single-thread asynchronous IO with high availability and scalability.
• Lightweight (~500 lines) and powerful by leveraging python builtin asyncio library.
• No additional library is required. All codes are in Pure Python.
• Automatically detect incoming traffic: HTTP/Socks/Shadowsocks/Redirect.
• Specify multiple remote servers for outcoming traffic: HTTP/Socks/Shadowsocks.
• Unix domain socket support for communicating locally.
• Basic authentication support for all three protocols.
• Regex pattern file support to route/block by hostname matching.
• SSL connection support to prevent Man-In-The-Middle attack.
• Encryption cipher support to keep communication secure. (chacha20, aes-256-cfb, etc)
• Shadowsocks OTA (One-Time-Auth) experimental feature support.
• Basic statistics for bandwidth and total traffic by client/hostname.
• PAC support for automatically javascript configuration.
• Iptables NAT redirect packet tunnel support.
• PyPy3.3 v5.5 support to enable JIT speedup.

Python3

Python 3.5 added new syntax async def and await to make asyncio programming easier. Python 3.6 added new syntax formatted string literals. This tool was to demonstrate these new syntax, so the minimal Python requirement was 3.6.

From pproxy 1.1.0, the minimal Python requirement is 3.3, since old python versions are still widely used and PyPy3 only has 3.3 support currently. Python 2 will not be supported in the future.

Installation

$ pip3 install pproxy

PyPy3

$ pypy3 -m ensurepip

$ pypy3 -m pip install asyncio pproxy

Requirement

pycryptodome is an optional library to enable faster (C version) cipher encryption. pproxy has many built-in pure python ciphers without need to install pycryptodome. They are lightweight and stable, but a little slow. After speed up with PyPy, the pure python ciphers can achieve similar performance as pycryptodome (C version). If you care about cipher performance and don't run in PyPy, just install pycryptodome to enable faster ciphers.

These are some performance comparisons between Python ciphers and C ciphers (process 8MB data totally):

$ python3 speed.py chacha20

chacha20 0.6451280117034912

$ pypy3 speed.py chacha20-py

chacha20-py 1.3277630805969238

$ python3 speed.py chacha20-py

chacha20-py 48.85661292076111

Usage

$ pproxy -h usage: pproxy [-h] [-i LISTEN] [-r RSERVER] [-b BLOCK] [-v] [--ssl SSLFILE] [--pac PAC] [--get GETS] [--version]

Proxy server that can tunnel among remote servers by regex rules. Supported protocols: http,socks,shadowsocks,redirect

optional arguments:

-h, --help	show this help message and exit
-i LISTEN	proxy server setting uri (default: http+socks://:8080/)
-r RSERVER	remote server setting uri (default: direct)
-b BLOCK	block regex rules
-v	print verbose output
--ssl SSLFILE	certfile[,keyfile] if server listen in ssl mode
--pac PAC	http PAC path
--get GETS	http custom path/file
--version	show program's version number and exit

Online help: <https://github.com/qwj/python-proxy>

URI Syntax

{scheme}://[{cipher}@]{netloc}[?{rules}][#{auth}]

• scheme

  • Currently supported scheme: http, socks, ss, ssl, secure. You can use + to link multiple protocols together.

    http:	http protocol
    socks:	socks5 protocol
    ss:	shadowsocks protocol
    redir:	redirect protocol (iptables nat)
    ssl:	communicate in (unsecured) ssl
    secure:	comnunicate in (secured) ssl

  • Valid schemes: http://, http+socks://, http+ssl://, ss+secure://, http+socks+ss://

  • Invalid schemes: ssl://, secure://

• cipher

  • Cipher is consisted by cipher name, colon ':' and cipher key.

  • Full supported cipher list: (Pure python ciphers has ciphername suffix -py)

    Cipher	Key Length	IV Length	Score (0-5)
    table-py	any	0	0 (lowest)
    rc4, rc4-py	16	0	0 (lowest)
    rc4-md5 rc4-md5-py	16	16	0.5
    chacha20 chacha20-py	32	8	5 (highest)
    chacha20-ietf-py	32	12	5
    salsa20 salsa20-py	32	8	4.5
    aes-128-cfb aes-128-cfb-py aes-128-cfb8-py aes-128-cfb1-py	16	16	3
    aes-192-cfb aes-192-cfb-py aes-192-cfb8-py aes-192-cfb1-py	24	16	3.5
    aes-256-cfb aes-256-cfb-py aes-256-ctr-py aes-256-ofb-py aes-256-cfb8-py aes-256-cfb1-py	32	16	4.5
    camellia-256-cfb camellia-192-cfb camellia-128-cfb	32 24 16	16 16 16	4 4 4
    bf-cfb bf-cfb-py	16	8	1
    cast5-cfb	16	8	2.5
    des-cfb	8	8	1.5
    rc2-cfb-py	16	8	2
    idea-cfb-py	16	8	2.5
    seed-cfb-py	16	16	2

  • Some pure python ciphers (aes-256-cfb1-py) is quite slow, and is not recommended to use without PyPy speedup. Try install pycryptodome and use C version cipher instead.

  • To enable OTA encryption with shadowsocks, add '!' immediately after cipher name.

• netloc

  • It can be "hostname:port" or "/unix_domain_path". If the hostname is empty, server will listen on all interfaces.
  • Valid netloc: localhost:8080, 0.0.0.0:8123, /tmp/domain_socket, :8123

• rules

  • The filename that contains regex rules

• auth

  • The username, colon ':', and the password

Examples

We can define file "rules" as follow:

#google domains

(?:.+.)?google.*.com

(?:.+.)?gstatic.com

(?:.+.)?gmail.com

(?:.+.)?ntp.org

(?:.+.)?glpals.com

(?:.+.)?akamai.*.net

(?:.+.)?ggpht.com

(?:.+.)?android.com

(?:.+.)?gvt1.com

(?:.+.)?youtube.*.com

(?:.+.)?ytimg.com

(?:.+.)?goo.gl

(?:.+.)?youtu.be

(?:.+.)?google..+

Then start the pproxy

$ pproxy -i http+socks://:8080 -r http://aa.bb.cc.dd:8080?rules -v

http www.googleapis.com:443 -> http aa.bb.cc.dd:8080

socks www.youtube.com:443 -> http aa.bb.cc.dd:8080

http www.yahoo.com:80

DIRECT: 1 (0.5K/s,1.2M/s) PROXY: 2 (24.3K/s,1.9M/s)

With these parameters, this utility will serve incoming traffic by either http/socks5 protocol, redirect all google traffic to http proxy aa.bb.cc.dd:8080, and visit all other traffic locally.

To bridge two servers, add cipher encryption to ensure data can't be intercepted. First, run pproxy locally

$ pproxy -i ss://:8888 -r ss://chacha20:[email protected]:12345 -v

Next, run pproxy.py remotely on server "aa.bb.cc.dd"

$ pproxy -i ss://chacha20:cipher_key@:12345

By doing this, the traffic between local and aa.bb.cc.dd is encrypted by stream cipher Chacha20 with key "cipher_key". If target hostname is not matched by regex file "rules", traffic will go through locally. Otherwise, traffic will go through the remote server by encryption.

A more complex example:

$ pproxy -i ss://salsa20!:complex_cipher_key@/tmp/pproxy_socket -r http+ssl://domain1.com:443#username:password

It listen on the unix domain socket /tmp/pproxy_socket, and use cipher name salsa20, cipher key "complex_cipher_key", and enable explicit OTA encryption for shadowsocks protocol. The traffic is tunneled to remote https proxy with simple authentication. If OTA mode is not specified, server will allow both non-OTA and OTA traffic. If specified OTA mode, server only allow OTA client to connect.

To establish an ssl tunnel to a remote server on port 443 through an http proxy, specify -p option:

$ pproxy -i http+socks://:8080 -r http+ssl://aa.bb.cc.dd:443 -p http://proxy_address:8080#username:password

If you want to listen in SSL, you must specify ssl certificate and private key files by parameter "--ssl", there is an example:

$ pproxy -i http+ssl://0.0.0.0:443 -i http://0.0.0.0:80 --ssl server.crt,server.key --pac /autopac

It listen on both 80 HTTP and 443 HTTPS ports, use the specified certificate and private key files. The "--pac" enable PAC support, so you can put https://yourdomain.com/autopac in your device's auto-configure url.

An iptable NAT redirect example:

$ iptables -t nat -A OUTPUT -p tcp --dport 80 -j REDIRECT --to-ports 5555

$ pproxy -i redir://:5555 -r http://remote_http_server:3128 -v

This example illustrates how to redirect all local output tcp traffic with destination port 80 to localhost port 5555 listened by pproxy, and then tunnel the traffic to remote http proxy.