ex encrypted script
Forgive me if this is a stupid question. I'm using AT&T unix Version 5 release 3.2.2 ( UNIX System V/386 Release 3.2) I have several simple scripts that are simple yet handle important realtime call proccessing tasks and remote control operations. These programs are my programs but are running on a system that is dialed into by the vendor once in a while. Is there a way to encrypt a script yet still allow it to be runnable? I know that the simple answer is to write it in C and compile it but I don't have the means of doing that at the moment. (i.e. there is not compiler on the system) I thought of a few simple protections but they all involve decrypting before running. Dr0id ( Computer Consulting & Management ) (P.O. Box 421 Cambria, IL 62915-0421) -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.2 mQENAzCsIi4AAAEH/1hb5+tO/n99Nbppf0ImLJ6AaVZ3NlZP0ZHwRQor00uA129i d4zWixNXxc8t2auaqN+asV99LpIip3/nQzBnjydiumeBdGLF2PR9+6X8X/RrqKa1 dVIukxM5Agg2eM6ih+0J38hgKJ3qzKXSz6sjYmpaxvbXZoHHOLUk/ZtHUKvvEyPw hnJEYnut8NUnIeK56lqeqRw86yoeRKymbfCdjdpgeY2aRwK2FJts8sbb7Fs10s4y jgxWIxIipBznbGUTh1hb2XrLGPENwk3E/qqXQJEsrySbtwdl6VgTVQjhDDEJMitL DYeiQ3W5EgxfcdbM1j2FwYu3P/dM6Y0I8xLMYT0ABRG0NmFuZHIwaWRAb2ljdTgx Mi5jb20gKG9pY3U4MTIuY29tIHN5c3RlbSBhZG1pbmlzdHJhdG9yKYkBFQMFEDCs LO90C7R/GkJcSQEB01cH/0KC3sd+u4OxMku5378SJktoN6QIQYLJ7uVbuV4S51yK NAotCGf4Wl6wwjynzZvXKU0H87oDuMiq7FybgMNL2n+4bQIZi0iz0lIuzwoMDu63 NrHUW9Kz42pOnhrEhrdkHhHL9O5GgD1yc40fJ3qw5h7LQEjDxgypyw0IFILFc34u LeRLliNibxKp8JwAxXNHWSgxu28TQvmnkHi0AHP6tJ/uZYe+4dqJtrMMsYFjzZaz DPmxD+dzbTwlQKtJaP1ZkDI0Sr072wrZDv+G86GyGBMX2lpSafpRitnxuUttjU9o wsQ9Qo5xiH1nZRCs/bDzJe/gng+GHzevixDIITurtNA= =SgPT -----END PGP PUBLIC KEY BLOCK-----
Jason Rentz wrote: | Forgive me if this is a stupid question. Hmmm. Will you pay us? | I'm using AT&T unix Version 5 release 3.2.2 ( UNIX System V/386 Release 3.2) [...] | Is there a way to encrypt a script yet still allow it to be runnable? I | know that the simple answer is to write it in C and compile it but I don't | have the means of doing that at the moment. (i.e. there is not compiler on | the system) | | I thought of a few simple protections but they all involve decrypting before | running. Ever hear of chmod? chown? Adam -- "It is seldom that liberty of any kind is lost all at once." -Hume
-----BEGIN PGP SIGNED MESSAGE----- Hello andr0id@midwest.net (Jason Rentz) and Cypherpunks Dr0id wrote:
I have several simple scripts that are simple yet handle important realtime call proccessing tasks and remote control operations. These programs are my programs but are running on a system that is dialed into by the vendor once in a while.
The problem will be that a superuser can do just about anything...
Is there a way to encrypt a script yet still allow it to be runnable? I ...
Well, what's wrong with pgp -f | /bin/sh ? Obviously, it still decrypts before use, and may or may not be useful depending on your application, but it never has a file with the unencrypted script around.
I thought of a few simple protections but they all involve decrypting before running.
It depends on what you want to prevent: copying the scripts, running them, understanding them, or what? To prevent copying/running them, you can use the above script, but you'll have to type in the passphrase each time (checking that noone is watching you, which is impossible with a determined su). If you just want them to not understand, obfuscation should suffice. (But reverse-engineering can still be applied.) (On the "supply useless source" subthread, it is possible to define the term "source code" so as to disallow such obfuscation. See the GNU GPL ("copyleft") licence for an example.) Adiau Jiri - -- If you want an answer, please mail to <jirib@cs.monash.edu.au>. On sweeney, I may delete without reading! PGP 463A14D5 (but it's at home so it'll take a day or two) PGP EF0607F9 (but it's at uni so don't rely on it too much) -----BEGIN PGP SIGNATURE----- Version: 2.6.2i iQCVAwUBMN0vfyxV6mvvBgf5AQGHkwP9EXLywkYYY6yNEAD3psLr/mbd7ACDe9hF NxDdu1LRQqtTmRx2GaozIEg2QWBaADEZ3TP7WyQyN9g81mC5bPk6Ys7imCvSDYW5 U1qg6MuE/biLlKuScE0AlpPeeKmqwSdG8bo8IsnMyyBnaeN1mBvfXVbwXzkpgJ7O 3IwGHbmB/wg= =+g0v -----END PGP SIGNATURE-----
On Wed, 20 Dec 1995, Jason Rentz wrote:
Forgive me if this is a stupid question.
I'm using AT&T unix Version 5 release 3.2.2 ( UNIX System V/386 Release 3.2)
I have several simple scripts that are simple yet handle important realtime call proccessing tasks and remote control operations. These programs are my programs but are running on a system that is dialed into by the vendor once in a while.
Is there a way to encrypt a script yet still allow it to be runnable? I know that the simple answer is to write it in C and compile it but I don't have the means of doing that at the moment. (i.e. there is not compiler on the system)
You can try something similar to what gzexe does, but...
I thought of a few simple protections but they all involve decrypting before running.
...unless the CPU has built in decryption this will be a necessity. A compromise might be to put this into the kernel zerucha@shell.portal.com finger zerucha@jobe.portal.com for PGP key
participants (4)
-
Adam Shostack -
andr0id＠midwest.net -
Jiri Baum -
Tom Zerucha