Shell Programming and Scripting

What Operating System and version are you using?
What Shell are you using?

The script in post #1 has appeared on many boards. For example

Can we hide the code of a Shell Script?

Is is dangerous to cut/paste code you find on the internet unless you understand that code.

Why do you want to obfuscate or encrypt shell script? There is really no substitute for correct file permissions and access lists.

---------- Post updated at 16:43 ---------- Previous update was at 16:39 ----------

To my mind the /dev/stdin and the trailing pipe character are surplus.

Also in most versions of "tr" there must be exactly the same number of characters either side. So your "key" would probably be 52 characters (it depends on the character set).

yes i roughly understand it, and i'm running it on cygwin so i'm not too bothered about any dangers. I want to encrypt or obfuscate stuff because somebody said to me that I won't be able to. I know that anyone can easily decrypt it if they bother having a go.

I did try it without the /dev/stdin | originally but it said that it was expecting something after it so wouldn't work. I added the pipe and the error disappeared. the key variable is as you describe it.

The problem is how I'm ending the script. the actual encrypted script is fine. after the #!/ova/fu there is the encrypted #!/bin/bash. This is the full code though, feel free to criticise how bad I am at this.

the 'scrypt' variable is the path of the script that is to be encrypted
the 'key' variable is the encryption key.

Code:

#BACKUP
cat $scrypt > $scrypt.old
#ENCRYPTER
cp $scrypt temps1.txt
cat temps1.txt | tr 'a-z' \""$key"\" > $scrypt
rm temps1.txt
#DECRYPTER 
cp $scrypt tempscrypt.txt
echo "#!/bin/sh
tr 'a-z'" \
" \""$key"\" <<EOF_EOF | sh /dev/stdin |" > tempscrypt.txt
echo "#!/ova/fu" >> tempscrypt.txt
cat $scrypt >> tempscrypt.txt
echo 'EOF_EOF' >> tempscrypt.txt
cp tempscrypt.txt $scrypt
rm tempscrypt.txt
echo ""
echo "Done."
read -p "Press enter to exit..."
exit

I think methyl got it. Get rid of that trailing "/dev/stdin | ". The trailing | is especially bad.

ok its working now. thanks everyone!

Because I cannot believe that the code in post #9 is the finished product, please post the final version of the code.

What is that extra pipe for? You're not piping the shell's output into anything that I can see...