Comment section over SSH

2024-10-22 - 2 minutes

A while ago I saw a blog that had a comment section where you could send messages over ssh. It noted that you should use your own username but sadly it was broken by the time I found it.

I wanted to implement something like this for a while and finally got to do it.

You can try it now by ssh-ing into this server with the user “comment”. Username entry comes afterwards.

It’s backed by a simple sqlite file and the script is self-contained and only needs libc and libsqlite3 to work.

You can find the full script here.

To get this to work you have to create a user with password login enabled. The actual password is optional and can be left empty. Up to you.

• Compile the scriptlet e.g. like such: gcc -O2 -static comment.c -o comment -lsqlite3
• Create a proxy command that invokes the above created command with a path to the sqlite file
• Create the user that has write permissions to the DB folder
• Set his shell to use the proxy command
• Enable password login in your sshd server config (PasswordAuthentication yes, PermitEmptyPasswords yes)

The resulting user should look something like this comment:x:9000:9001:comments:/var/lib/comment:/usr/bin/comment.sh

The proxy command could look like this:

#!/bin/sh

comment /var/lib/comment/comments.sqlite

If you need assistance, just leave me a comment :)