bhyvex/sshconfigfs

A FUSE filesystem to dynamically build SSH client config

SSHConfigFS

SSHConfigFS is a FUSE filesystem to build SSH client config files on–the–fly.

If your ~/.ssh/config is anything like mine, then it's pretty long (and only seems to grow). Rather than having to continue managing one big file, I wrote this FUSE filesystem to instead build a config "file" dynamically from many smaller logical chunks.

OS Requirements

OSX

Python 2.7 and the osxfuse package (Fuse4X also works, but that project is being merged with osxfuse).

Linux

You will need to install fusypy with pip, the alternative python package installer.

Ubuntu/Linux Mint

https://github.com/terencehonles/fusepy/issues/30

First install pip:

sudo apt-get install python-pip

Install wheel package using pip repo:

sudo pip install wheel

Install fusepy package using pip repo:

sudo pip install fusepy

OR

Install fusepy package using github sources:

sudo pip install git+https://github.com/dsoprea/fusepy.git

Setup fusepy with pip wheel:

sudo pip wheel fusepy

Run the script with python2.7.x:

python2.7 sshconfigfs.py

PS: you might need to give read access to /etc/fuse.conf:

sudo chmod 644 /etc/fuse.conf

sshconfigfs needs no admin rights.

Installation

On OSX, first install osxfuse (if you're using Homebrew it's available with brew install osxfuse), then install the python requirements: pip install -r requirements.txt installs only fusepy.

Running the filesystem

To start, run the sshconfigfs.py script. There are no arguments, yet, and it will run in the foreground.

The directory ~/.ssh/config.d/ is monitored for changes to its mtime. Whenever one of the files inside ~/.ssh/config.d/ changes, it triggers re-generation of the combined config.

For a chunk of config to be included in the final output, it must start with a number. In ~/.ssh/config.d/ I keep several files:

10_base
15_tunnels
20_workhosts
30_personalhosts

These files are combined in the order they appear above, using shell–style globbing, into a single "file" contained within the FUSE mountpoint ~/.sshconfigfs/ (the combined file is called config).

You could create a symbolic link from ~/.ssh/config to the generated ~/.sshconfigfs/config file, so ssh can find it, or use the -F argument to ssh to point it directly at the generated file.

To give another example of use, I have a crontab entry periodically generating ssh Host… config chunks—using data from VPS provider's APIs—which are then written to files inside ~/.ssh/config.d/. This keeps my config up to date without my having to manually manage a large, somewhat dynamic, list of hosts.

Run at startup

I use OSX. To keep SSHConfigFS running, I use the included .plist file to tell OSX's launchd to run the sshconfigfs.py script to mount the filesystem.

mkdir -p ~/Library/LaunchAgents

Edit the com.markhellewell.SSHConfigFS.plist file and change the path to the sshconfigfs.py script. Then:

cp com.markhellewell.SSHConfigFS.plist ~/Library/LaunchAgents/
launchctl load -w ~/Library/LaunchAgents/com.markhellewell.SSHConfigFS.plist

This will keep the SSHConfigFS mounted, as your user, forever.

TODO

• dæmon mode support (at the moment will only run in the foreground)
• take arguments to configure configd_dir etc.
• pie shop?

License

The BSD License. See LICENSE.