Encrypt and password-protect execution of any bash script

echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
(Please see sample output for usage) script.bash is your script, which will be crypted to script.secure script.bash --> script.secure You can execute script.secure only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner.
Sample Output
$ cat script.bash 

#!/bin/bash
echo "Hello, world"

$ echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
Enter passphrase:
Repeat passphrase:

$ ./script.secure 
Enter passphrase:

Hello, world

$ cat script.secure 
eval "$(dd if=$0 bs=1 skip=69 2>/dev/null|gpg -d 2>/dev/null)"; exit
%6&A2%&F%&B%&%4&%

1 Alternatives + Submit Alt

  • (Please see sample output for usage) Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.: myscript --> myscript.crypt You can execute myscript.crypt only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Sorry for the chmod on parentheses, I dont like "-" at the end. Thanks flatcap for the subshell abbreviation to /dev/null Show Sample Output


    6
    read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
    rodolfoap · 2013-03-10 08:59:45 9

What Others Think

Nicely done !
erix · 288 weeks and 6 days ago
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yeiuoisdf · 288 weeks and 5 days ago
Your command is wrong. Hint: What is script.bash?
betsubetsu · 288 weeks and 5 days ago
betsu{,} : click on Sample Output with the right button of your mouse and you see how to use the command. You need some input script to encrypt, in the example, script.bash.
rodolfoap · 288 weeks and 5 days ago
very good, I like it
liuwei000000 · 288 weeks and 1 day ago

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