µProxy

A minimal, memory-efficient HTTP/HTTPS proxy server designed to run in memory-constraint environments.
Originally written for MicroPython, now compatible with CPython.

Usage (MicroPython):

import uasyncio as asyncio
import uproxy
proxy = uproxy.uProxy(ip='0.0.0.0', port=8765)
asyncio.run(proxy.run())

Usage (CPython):

cproxy.py is a CPython-compatible wrapper of uproxy.py for running uproxy in console.

cproxy.py [-h] [-v] [--ip IP] [--port PORT] [--bind BIND]
          [--bufsize BUFSIZE] [--maxconns N] [--backlog M]
          [--timeout TIMEOUT] [--loglevel LOGLEVEL]
          [--auth AUTH] [--upstream UPSTREAM]

See next section for parameter usage.

$ python3 cproxy.py --ip 0.0.0.0 --port 8765
Listening on 0.0.0.0:8765
CONNECT 192.168.1.230:54309     ==>     ifconfig.me:443
GET     192.168.1.230:54312     ==>     ifconfig.me:80
CONNECT 192.168.1.230:54315     ==>     www.google.com:443

To use cproxy.py in code:

import asyncio
import cproxy
proxy = cproxy.uProxy()
asyncio.run(proxy.run())

API docs:

uproxy.uProxy(ip='0.0.0.0', port=8765, bind=None, bufsize=8192, maxconns=0, backlog=100, timeout=30, ssl=None, loglevel=1, acl_callback=None, auth=None, upstream=None)

Initialize proxy server
- ip - server ip
- port - server port
- bind - ip address for outgoing connections to bind to
- bufsize - buffer size of each connection, in bytes
- maxconns - max number of accepted connections server can handle, 0 to disable
- backlog - max number of unaccepted connections waiting to be processed
- timeout - connection timeout, in seconds
- loglevel - log level (0-quiet, 1-info, 2-debug)
- ssl - a SSLContext object to start a HTTPS server
- acl_callback - access control callback function
- auth - an 'user:password' pair that clients need to provide in order to authenticate with server
- upstream - an 'ip:port' pair to connect to as an upstream HTTP proxy
uProxy.run()

Start proxy server.
Need to run in an asyncio event loop
uProxy.acl_callback

The access control callback function takes a 4-tuple input (source ip/port and destination ip/port).
Return True to allow current connection to pass, return False to block it.
Default value None means always allow all connection to pass.
```
def acl_callback(src_ip: str, src_port: int, dst_ip: str, dst_port: int) -> bool
```

Other:

To use it with MicroPython, only need to copy uproxy.py.
To use it with CPython, copy both files and use cproxy.py.
cproxy.py replaces some core logic of uproxy.py, making it run much faster, at the expense of 2x memory consumption.
For detail usage, please refer to examples/

Todo: