sslh -- A ssl/ssh multiplexer
=============================

`sslh` accepts connections on specified ports, and forwards
them further based on tests performed on the first data
packet sent by the remote client.

Probes for HTTP, TLS/SSL (including SNI and ALPN), SSH,
OpenVPN, tinc, XMPP, SOCKS5, are implemented, and any other
protocol that can be tested using a regular expression, can
be recognised. A typical use case is to allow serving
several services on port 443 (e.g. to connect to SSH from
inside a corporate firewall, which almost never block port
443) while still serving HTTPS on that port. 

Hence `sslh` acts as a protocol demultiplexer, or a
switchboard. With the SNI and ALPN probe, it makes a good
front-end to a virtual host farm hosted behind a single IP
address.

`sslh` has the bells and whistles expected from a mature
daemon: privilege and capabilities dropping, inetd support,
systemd support, transparent proxying, chroot, logging, 
IPv4 and IPv6, TCP and UDP, a fork-based and a select-based 
model, and more.

Install
=======

Please refer to the [install guide](doc/INSTALL.md).


Configuration
=============

Please refer to the [configuration guide](doc/config.md).



Docker image
------------

How to use

---

Build docker image

    make docker


```bash
docker run \
  --rm \
  -it \
  sslh:latest \
  --listen=0.0.0.0:443 \
  --ssh=hostname:22 \
  --tls=hostname:443
```

docker-compose example

```
version: "3"

services:
  sslh:
    image: sslh:latest
    hostname: sslh
    ports:
      - 443:443
    command: --listen=0.0.0.0:443 --tls=nginx:443 --openvpn=openvpn:1194
    depends_on:
      - nginx
      - openvpn

  nginx:
    image: nginx

  openvpn:
    image: openvpn
```

Comments? Questions?
====================

You can subscribe to the `sslh` mailing list here:
<https://lists.rutschle.net/mailman/listinfo/sslh>

This mailing list should be used for discussion, feature
requests, and will be the preferred channel for announcements.

Of course, check the [FAQ](doc/FAQ.md) first!