-WARNING: The method showed here could not prevent the actual execution of “rm -rf” if the “UNIX vandal” is clever enough. Proceed at your own risk, and make backups! -
+ +WARNING: The method showed here could not prevent the actual execution of "rm -rf" if the "UNIX vandal" is clever enough. Proceed at your own risk, and make backups! + -I like Rick Astley late 80’s songs, and you can see them here in my Spotify:
++I like Rick Astley late 80's songs, and you can see them here in my Spotify: +
-
+
+
I like rickrolling people myself too, especially if they’re trying to delete my entire /home directory or, even worse, /. Since I learned how to use the alias built-in, I wanted a way to prevent that random people tinkering with my laptop (that I may forgot to lock) could delete potentially important stuff, just for fun or boredom.
+ I like rickrolling people too, especially if they are trying to delete my entire
+ /home directory or, even worse, /. Since I learned
+ how to use the alias built-in, I wanted a way to prevent that
+ random people tinkering with my laptop (that I may forgot to lock) could
+ delete potentially important stuff, just for fun or boredom.
+
The method that I’ll show will lock any rm command runned in both recursive and force mode, so rm -rf, rm -f -r and rm -r --force are all blocked, even if they are launched by sudo. I’m going to alias the rm command in /etc/profile /etc/bash.bashrc and in /etc/zsh/zshrc (I’m a zsh user) so that the rickroll will be possible from all users, even root and the ones with a brand new bashrc or zshrc. Here is the code I appended to those files:
+ The method that I will show will lock any rm command runned in
+ both recursive and force mode, so rm -rf, rm -f -r
+ and rm -r --force are all blocked, even if they are runned with
+ sudo. I am going to alias the rm command in
+ /etc/profile, /etc/bash.bashrc and in
+ /etc/zsh/zshrc (I am a zsh user) so that the rickroll will be
+ possible from all users, even root and the ones with a brand new
+ .bashrc or .zshrc. Here is the code I appended to
+ those files:
+
alias rm=/bin/rmAlias
alias sudo='sudo ' # this enables aliases in sudo, see http://askubuntu.com/questions/22037/aliases-not-available-when-using-sudo
Since alias is not able to control the flags of the aliases (see here), we’re going to redirect each call of rm to /bin/rmAlias, that would run the command if it’s safe. I didn’t use a function because it’s a bit tricky to make that work with sudo. So, let’s see the code I put in rmAlias:
+ Since alias is not able to control the flags of the aliases (see
+ here, we are going to redirect each call of rm to
+ /bin/rmAlias, that would run the command if it is safe. I did
+ not use a function because it is a bit tricky to make that work with
+ sudo. So, let's see the code I put in rmAlias:
+
#! /bin/bash
# Rickroll whoever tries to desert this system, even root.
# To achieve this, set the appropriate aliases even in /etc/profile and similars.
@@ -154,16 +185,35 @@ done
# If it's safe, just run rm
/bin/rm "$@"
exit $?
It may look messy to a UNIX guy more experienced than me, but it works. The getopts built-in sees if both the -r and the -f flags are used and, if so, it starts rickroll(), which opens with xdg-open that amazing clip from RickAstleyVEVO. From line 30 and below, the script checks if the --force flag is used instead of -f.
+ It may look messy to a UNIX guy more experienced than me, but it
+ works. The getopts built-in sees if both the -r and
+ the -f flags are used and, if so, it starts
+ rickroll(), which opens with xdg-open that amazing
+ clip from RickAstleyVEVO. From line 30 and below, the script checks
+ if the --force flag is used instead of -f.
+
Give execute permissions to the script we’ve just created:
++ Let's give execution permissions to the script we have just created: +
+
# chmod +x /bin/rmAlias
Restart your shell, and enjoy. If you want to test safely, I suggest trying to run rm -rf with no folders or one nonexistant, since this script stop even these commands.
+ Restart your shell, and enjoy. If you want to test safely, I suggest trying
+ to run rm -rf with no folders or a nonexistant one, since this
+ script stops even these commands.
+
If you want even more security, you can rename this script to /bin/rm and move the original one in some other place, getting rid of all the aliases. I prefer the solution above because it’s tidier: you haven’t to move anything. In fact, this could be just an AUR package…
+ If you want even more security, you can rename this script to
+ /bin/rm and move the original one in some other place, getting rid of all the aliases. I prefer the solution above because it's tidier: you haven't to move anything. In fact, this could be just an AUR package...
+