Bash scripts encryption and passphrase-protection

scrypt(){ [ -n "$1" ]&&{ echo '. <(echo "$(tail -n+2 $0|base64 -d|mcrypt -dq)"); exit;'>$1.scrypt;cat $1|mcrypt|base64 >>$1.scrypt;chmod +x $1.scrypt;};}
This function will encrypt a bash script and will only execute it after providing the passphrase. Requires mcrypt to be installed on the system.
Sample Output
$ cat hello
case "$1" in
""|-h) echo "This is the fantastic Hello World. Try this:" $(basename $0) "[entity]" ;;
moon) echo Good night.  ;;
sun) echo Good morning.  ;;
world) echo "Hello, world!" ;;
*) echo Hi, $@.  ;;

$ scrypt hello
Enter the passphrase (maximum of 512 characters)
Please use a combination of upper and lower case letters and numbers.
Enter passphrase:
Enter passphrase:
Stdin was encrypted.

$ cat hello.scrypt
. <(echo "$(/usr/bin/tail -n+2 $0|base64 -d|mcrypt -dq)");exit;

$ ./hello
This is the fantastic Hello World. Try this: hello [entity]

$ ./hello.scrypt
Enter passphrase:
This is the fantastic Hello World. Try this: hello.scrypt [entity]

$ ./hello world
Hello, world!

$ ./hello.scrypt world
Enter passphrase:
Hello, world!

What Others Think

I had some trouble running this on my OSX laptop with zsh so I added the following modifications to my zshrc: function scrypt(){ [ -n "$1" ]&&{ echo '(echo "$(tail -n+2 $0|base64 -D -i - |mcrypt -d )") | bash; exit;'>$1.scrypt;cat $1|mcrypt|base64 >>$1.scrypt;chmod +x $1.scrypt;}; } Thanks! Enjoyed it
bbarrows · 210 weeks and 3 days ago
sophiacharles · 202 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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