Shell Programming and Scripting

How to get the original password from "bXlwYXNzd29yZAo=" ?

By carefully reading the man page of "base64", until, upon chance, stumbling upon the description of the secret "-d" (decode) command line option and subsequently applying this arcane knowledge to your command line.

I hope this helps.

bakunin

What would be the point of storing an encrypted password? Is this so that it can be checked against user input?

A possible better way might be:-Obviously you would have to store the output from a previous sum or md5sum in your script, but that is less likely to be cracked.


Would that help, OR is everyone going to shoot me down for doing something really daft. I hope it's helpful but I would like to be corrected if necessary.



Kind regards,
Robin

First off: this is perhaps the most ingenious way of being most secure in employing insecure methods in general. Sorry for this rather double-edged compliment, but you have to be aware that there are secure methods and there are other (not secure) methods. If you decide against secure methods you will always be able to move farther up the security scale, but only to some extent - principally insecure will always remain principally insecure, regardless of what you do.

Your method suffers from the fact that scripts are readable. I can extract the necessary md5sum from it, create a fitting PW offline (using all sorts of methods: dictionary attacks, ...) and then feed that PW into the script.

Still, your method is better than many others i have seen suggested in similar threads here and elsewhere.

I hope this helps.

bakunin

Note that a user's encrypted login password is created using crypt() exactly as you suggested and the system used to store the encrypted string in plain text in /etc/passwd (which is readable by everyone so tools like ls can decode the user-IDs and group-IDs returned by stat() into user and group names in long listings). Many, many moons ago, the actual encrypted passwords were moved into /etc/shadow which is readable only by root to avoid the problem bakunin mentioned in post #11.

I quite agree that this is not a great solution, but hopefully it's better than some. I would always prefer to use the tool designed for the job, (e.g. SSH keys) but as we still don't know the real purpose I'm not sure what the best tool is.

Are we discussing it here too:- https://www.unix.com/shell-programmin...#post302983344

It seems rather similar to me.


Robin

A little late into this thread but wouldn't the '=' be a bit of a give away?
Just a thought...

I know it is a padding character...

EDIT:
Also there would be a newline added using echo...
echo -n "mypassword" | base64
gives...
bXlwYXNzd29yZA==