Transparent reverse proxy (mainly for HTTP and HTTPS) using python
You can install the requirements via python -m pip install -r requirements.txt, or look through the requirements file and add them via your package manager.
The server side can be started by running python -m ReverseProxy.server, try --help to see the usage string. For a simple example, listening for one virtual host, use:
python -m ReverseProxy.server --listenInterface 0.0.0.0 --listenPort=8080 vhost --hostname some.regex.com --socket /path/to/unix/socket
When a connection comes in with the SSL SNI or HTTP Host line matching the specified regex, the connection will get passed to through the socket specified
The python side can be started by running python -m ReverseProxy.client, try --help to see the usage string. For a simple example (non ssl) use:
python -m ReverseProxy.client --listenPort /path/to/unix/socket --application fully.qualified.python.name.of.twisted.application
Most other web servers can be used as clients, using an LD_PRELOAD library. The LD_PRELOAD library needs to intercept listening on some tcp port and instead listen on a UNIX socket. A simple LD_PRELOAD library is included. To set the proxy socket location, set REVERSE_PROXY_PORT=/path/to/unix/socket. For programs trying to listen on lots of sockets, set REVERSE_PROXY_PREFIX=/path/to/unix and it will make subfolders for each hostname/port combination (hex encoded).