r n s h  Shell over Reticulum

rnsh is a utility written in Python that facilitates shell sessions over Reticulum networks. It is based off the rnx utility that ships with Reticulum.

rnsh is still pretty raw; there are some things that are implemented badly, and many other things that haven't been built at all (yet). Signals (i.e. Ctrl-C) need some work, so have another terminal handy to send a SIGTERM if things glitch out.

One of the main drivers of complexity in the implementation is that the only reliable way I found to read live from stdin/stdout (as opposed to line by line) without blocking required using quite a bit of async code, while the RNS API is firmly synchronous.

Anyway, there's a lot of room for improvement.

Quickstart

Tested (thus far) on Python 3.11 macOS 13.1 ARM64. Should run on Python 3.6+ on Linux or Unix. WSL probably works. Cygwin might work, too.

• Activate a virtualenv
• pip3 install rnsh
  • Or from a whl release, pip3 install /path/to/rnsh-0.0.1-py3-none-any.whl
• Configure Reticulum interfaces, check with rnstatus
• Ready to run rnsh. The options are shown below.

Usage:
    rnsh [--config <configdir>] [-i <identityfile>] [-s <service_name>] [-l] -p
    rnsh -l [--config <configfile>] [-i <identityfile>] [-s <service_name>] 
         [-v...] [-q...] [-b] (-n | -a <identity_hash> [-a <identity_hash>]...) 
         [--] <program> [<arg>...]
    rnsh [--config <configfile>] [-i <identityfile>] [-s <service_name>] 
         [-v...] [-q...] [-N] [-m] [-w <timeout>] <destination_hash>
    rnsh -h
    rnsh --version

Options:
    --config DIR             Alternate Reticulum config directory to use
    -i FILE --identity FILE  Specific identity file to use
    -s NAME --service NAME   Listen on/connect to specific service name if not default
    -p --print-identity      Print identity information and exit
    -l --listen              Listen (server) mode
    -b --no-announce         Do not announce service
    -a HASH --allowed HASH   Specify identities allowed to connect
    -n --no-auth             Disable authentication
    -N --no-id               Disable identify on connect
    -m --mirror              Client returns with code of remote process
    -w TIME --timeout TIME   Specify client connect and request timeout in seconds
    -v --verbose             Increase verbosity
    -q --quiet               Increase quietness
    --version                Show version
    -h --help                Show this help

How it works

Listeners

Listener instances are the servers. Each listener is configured with an RNS identity, and a service name. Together, RNS makes these into a destination hash that can be used to connect to your listener.

Multiple listeners can use the same identity. As long as they are given different service names. They will have different destination hashes and not conflict.

Listeners must be configured with a command line to run (at least at this time). The identity hash string is set in the environment variable RNS_REMOTE_IDENTITY for use in child programs.

Listeners are set up using the -l flag.

Initiators

Initiators are the clients. Each initiator has an identity hash which is used as an authentication mechanism on Reticulum. You'll need this value to configure the listener to allow your connection. It is possible to run the server without authentication, but hopefully it's obvious that this is an advanced use case.

To get the identity hash, use the -p flag.

With the initiator identity set up in the listener command line, and with the listener identity copied (you'll need to do -p on the listener side, too), you can run the initiator.

I recommend staying pretty vanilla to start with and trying /bin/zsh or whatever your favorite shell is these days. The shell should start in login mode. Ideally it works just like an ssh shell session.

Roadmap

1. Plan a better roadmap
2. ?
3. Keep my day job

TODO

• Initial version
• Pip package with command-line utility support
• Publish to PyPI
• Improve signal handling
• Protocol improvements (throughput!)
• Test on several *nixes
• Make it scriptable (currently requires a tty)
• Documentation improvements