Show HN: Shittp – Volatile Dotfiles over SSH

103 pointsposted 8 hours ago
by sdovan1
(github.com)

57 Comments

sdovan1

8 hours ago

I often need to login to colleagues' machines at work, but I find that their settings are not what I am familiar with. So I wrote an SSH wrapper in POSIX shell which tars dotfiles into a base64 string, passes it to SSH, and decodes / setups on the remote temp directory. Automatically remove when session ends.

Supported: .profile, .vimrc, .bashrc, .tmux.conf, etc.

This idea comes from kyrat[1]; passing files via a base64 string is a really cool approach.

[1]: https://github.com/fsquillace/kyrat/

Joker_vD

5 hours ago

   scp my-precious-dotfiles remote:~
   trap 'ssh remote rm my-precious-dotfiles' EXIT
   ssh remote
Or you can even bake the trap into the remote bash's invocation, although that'd be a bit harder.

alsetmusic

5 hours ago

I came across something similar a few months ago. I pieced together a working hybrid by patching in parts from an older release with the latest version. I didn't ever work out if the latest version failed because of something in my environment or not, but I'm on a Mac fwiw.

https://github.com/cdown/sshrc

amelius

5 hours ago

Ok, but what if your colleague does not have Vim installed?

Wouldn't it make more sense to have a tool that brings files over to the local computer, starts Vim on them, and then copies them back?

sdovan1

5 hours ago

We usually work on the VM with daily-built ISO. For example, I would compile and upload Java program to the frontend team member's VM, and type "srt" for "systemctl restart tomcat."

Joker_vD

5 hours ago

That starts to sound like using VS Code in remote mode.

exe34

5 hours ago

Emacs in tramp mode.

QuinnyPig

5 hours ago

I can’t recall encountering a system in the last 15 years that didn’t have vim (or at least vi for esoteric things) on it.

foltik

4 hours ago

I have a python script [0] which builds and statically links my toolbox (fish, neovim, tmux, rg/fd/sd, etc.) into a self contained —-prefix which can be rsynced to any machine.

It has an activate script which sets PATH, XDG_CONFIG_HOME, XDG_DATA_HOME, and friends. This way everything runs out of that single dir and doesn’t pollute the remote.

My ssh RemoteCommand then just checks for and calls the activate script if it exists. I get dropped into a nice shell with all my config and tools wherever I go, without disturbing others’ configs or system packages.

[0] https://github.com/foltik/dots

stijnveken

4 hours ago

Is this available somewhere? I'm curious to see how this works.

foltik

4 hours ago

Published a minimal version and added a link! This implements everything I mentioned except for static linking, so YMMV depending on your C/CXX toolchain and installed packages.

Y_Y

7 hours ago

  tmp="$(mktemp -d)" && rsync -a --exclude='.ssh' user@host:~/.[!.]* "$tmp"/ && HOME="$tmp" exec "$SHELL"

grepfru_it

7 hours ago

I think this will copy your 9gb Mozilla cache directory as well? Still one liners like this is all you need lol

Bender

6 hours ago

My mozilla cache would be under ~/.mozilla/firefox. Is the nightly version moving to ~/.config?

Reason I say would be is that I disable disk cache among other things performed by Arkenfox [1]

[1] - https://github.com/arkenfox/user.js

lights0123

3 hours ago

Yes, Firefox 147 will respect XDG dirs.

grepfru_it

5 hours ago

What does config have to do with the one liner?

Bender

4 hours ago

Prevents some data from ending up in ~/.mozilla. We dont sync what does not exist.

grepfru_it

2 hours ago

My guy, the one liner as written copies all dot files. Mozilla included

Bender

2 hours ago

My guy, the one liner as written copies all dot files. Mozilla included

Exactly why I apply Sun Tzu methodology.

sigwinch

6 hours ago

Any sufficiently-advanced automated rsync would have a filter for caches.

grepfru_it

5 hours ago

Except only ssh is filtered. Just commenting on what I see, not what should be

Y_Y

4 hours ago

For sure, you need to exclude whatever "dotfiles" you don't want copied (or explicitly copy the ones you want), particularly caches and other giant hidden things.

sdovan1

5 hours ago

Overriding HOME variable is neat! Make things much easier.

imiric

7 hours ago

I use something similar.

It's surprising to me how many projects can be replaced with just a line or two of shell script. This project is a slightly more sophisticated shell script that exposes a friendlier UI, but I don't see why it's needed when the alternative is much simpler, considering the target audience.

goku12

7 hours ago

How about mounting your dotfiles directory (~/.config) or even your entire home directory on the remote system using SSHFS or NFS? I'm sure somebody would have tried it or some project may already exist. Any idea why that isn't as prevalent as copying your dotfiles over?

cl3misch

4 hours ago

That requires the remote machine to be configured to SSH into your local machine. In the scenario where OP's project is useful (SSH to foreign machines) I might not want that.

On the other hand, if the remote machine is mine, it will have my config anyway.

goku12

3 hours ago

There should be some way to mount a local directory onto a remote system without requiring the remote system to log in to the local system. SSH provides a secure bidirectional communication channel between the two systems. While we normally use sshfs to mount a remote directory to the local system, why should the reverse be impossible? Besides, you could also use NFS over SSH or TLS.

sigwinch

6 hours ago

I’m trying to imagine why sshfs mounting the less-capable remote onto the workstation would be blocked.

vbernat

6 hours ago

This would enable a lot of attacks.

goku12

6 hours ago

Could you elaborate?

oasisaimlessly

4 hours ago

Now anybody with root/sudo/physical access to the remote machine has full R/W access to your entire home directory.

goku12

3 hours ago

Well, what if it's a separate directory meant exclusively for remote systems alone? And what if the remote mount is read-only, perhaps with a writable layer on top using overlayfs that can be discarded on logout?

throw2772

6 hours ago

This reminds me - in a previous company I worked at, we had a bunch of old firewalls and switches that ran SSH servers without support for modern key exchange algorithms etc

One of the engineers wrote a shell alias called “shitssh”, which would call ssh with the right options to allow the old crufty crypto algorithms to be used. This alias got passed down to new members of the team like a family heirloom.

ghostly_s

an hour ago

People who choose such a noxious name for their project that it actually dissuades people who might otherwise be users think that says something about those prudish users, but it really says something about them.

yoan9224

3 hours ago

I love the concept but I'd be worried about security in enterprise environments. Some of the dotfiles (especially .bashrc) could override security policies or compliance settings that IT has configured.

That said, for personal servers this is brilliant. I've been using a git repo for dotfiles but having them automatically cleanup on disconnect is clever.

One improvement: consider using SSH's ProxyCommand or LocalCommand instead of wrapping SSH entirely. That way it works transparently with tools that call SSH directly (git, rsync, etc).

Also curious - does this handle tmux sessions properly? I often SSH in, start tmux, disconnect, then reconnect later. Would the dotfiles still be there?

drewr

5 hours ago

I didn't look closely at the project, but why take the extra step of base64? I do this all the time with tar by itself and it's wire-proof enough to work fine.

qudat

6 hours ago

I have a dotfiles git repo that symlinks my dotfiles. Then I can either pull the repo down on remote machine or rsync. I’m not sure why I would pick this over a git repo with a dotfiles.sh script

https://erock-git-dotfiles.pgs.sh/tree/main/item/dotfiles.sh...

montroser

5 hours ago

This is for when you have to ssh into some machine that's not yours, in order to do debugging or troubleshooting -- and you need your precious dotfiles while you're in there, but it would be not nice to scatter your config and leave it as a surprise for the next person.

This installs into temp dirs and cleans it all up when you disconnect.

Personally, my old-man solution to this problem is different: always roll with defaults even if you don't like them, and don't use aliases. Not for everyone, but I can ssh into any random box and not be flailing about.

Even with OP's neat solution, it's not really going to work when you have to go through a jump box, or have to connect with a serial connection or some enterprise audit loggable ssh wrapper, etc

Y_Y

4 hours ago

There's definitely something be said for speaking the common tongue, and being able to use the defaults when it's necessary. I have some nice customisations, but make a point of not becoming depwndent on them because I'm so often not in my own environment.

On the other hand, your comment has me wondering if ssh-agent could be abused to drag your config along between jump hosts and enterprise nonsense, like ti does forwarding of keys.

cyanf

4 hours ago

Why would you want to ssh into a machine that's not yours? That's a violation of the Computer Frauds and Abuse Act, up to 10 years in prison!

montroser

3 hours ago

I think you're joking, but to clarify -- not personally yours. A misbehaving worker box, an app server in the staging environment, etc. A resource owned by the organization for which you work, where it would not be appropriate for you to customize it to your own liking

otterley

4 hours ago

When you have permission to do so, it isn’t.

neocron

5 hours ago

I don't know, I just use the standard on my machine or on remote. Why bother to customize it all the time when you can't work without the customizations

est

6 hours ago

I wonder why are dofiles have to be on remote machines?

e.g. I type an alias, the ssh client expands it on my local machine and send complex commands to remote. Could this be possible?

I suppose a special shell could make it work.

Joker_vD

5 hours ago

> I wonder why are dofiles have to be on remote machines?

Because the processes that use them run on the remote machines.

> I type an alias, the ssh client expands it on my local machine and send complex commands to remote.

This is not how SSH works. It merely takes your keystrokes and sends them to the remote machine, where bash/whatever reads and processes them.

Of course, you can have it work the way you imagine, it's just that it'd require a very special shell on your local machine, and a whole RAT client on the remote machine, which your special shell should be intimately aware about. E.g. TAB-completion of files would involve asking the remote machine to send the dir contents to your shell, and if your alias includes a process substitution... where should that process run?

minitech

6 hours ago

> I suppose a special shell could make it work.

Working on it! :)

Remote machines usually don’t need to know your keystrokes or handle your line editing, either. There’s a lot of latency to cut out, local customization to preserve, and protocol simplification to be had.

tensegrist

8 hours ago

time to call the it team at work (on the phone) to ask them to add a new item to the software allowlist

grepfru_it

7 hours ago

Be careful, this will force your defaults over system defaults possibly overriding compliance or security settings. There are a few places I noticed where well-placed malware could hop in etc.

It’s not bad software, it’s also not mature. I’m currently on a phone and on vacation so this is the extent of my review. Maybe I’ll circle back around with some PRs next week

throw20251220

4 hours ago

More like shit toilet paper. Name like findtherapist.com

deadbabe

3 hours ago

Why call this Shittp? Is it to imply it’s actually shitty and just a proof of concept or fun project?